diff --git a/helm/rest/nico-rest/charts/nico-rest-api/templates/deployment.yaml b/helm/rest/nico-rest/charts/nico-rest-api/templates/deployment.yaml
index 2cb89cfff1..a18f765e13 100644
--- a/helm/rest/nico-rest/charts/nico-rest-api/templates/deployment.yaml
+++ b/helm/rest/nico-rest/charts/nico-rest-api/templates/deployment.yaml
@@ -47,6 +47,13 @@ spec:
           env:
             - name: CONFIG_FILE_PATH
               value: /app/config.yaml
+            {{- range $k, $v := .Values.extraEnv }}
+            {{- if has $k (list "CONFIG_FILE_PATH") }}
+            {{- fail (printf "extraEnv must not override chart-managed variable %s" $k) }}
+            {{- end }}
+            - name: {{ $k }}
+              value: {{ $v | quote }}
+            {{- end }}
           volumeMounts:
             - name: config
               mountPath: /app/config.yaml
diff --git a/helm/rest/nico-rest/charts/nico-rest-api/values.yaml b/helm/rest/nico-rest/charts/nico-rest-api/values.yaml
index 527ccd6ac5..7dc6d9ebb1 100644
--- a/helm/rest/nico-rest/charts/nico-rest-api/values.yaml
+++ b/helm/rest/nico-rest/charts/nico-rest-api/values.yaml
@@ -75,7 +75,8 @@ config:
     enabled: true
     port: 9360
   tracing:
-    enabled: false
+    # Gates the otelecho middleware and the Temporal client interceptor.
+    enabled: true
     serviceName: nico-rest-api
   # -- JWT issuers for authentication (mutually exclusive with keycloak)
   # When keycloak is disabled, at least one issuer must be configured.
@@ -100,3 +101,6 @@ config:
     rate: 10.0
     burst: 30
     expiresIn: 180
+
+# -- Extra container environment, name->value. Mainly for OTEL_* variables.
+extraEnv: {}
diff --git a/helm/rest/nico-rest/charts/nico-rest-workflow/templates/deployment-cloud-worker.yaml b/helm/rest/nico-rest/charts/nico-rest-workflow/templates/deployment-cloud-worker.yaml
index 387ffb0867..4dbde402d2 100644
--- a/helm/rest/nico-rest/charts/nico-rest-workflow/templates/deployment-cloud-worker.yaml
+++ b/helm/rest/nico-rest/charts/nico-rest-workflow/templates/deployment-cloud-worker.yaml
@@ -44,6 +44,13 @@ spec:
               value: /app/config.yaml
             - name: TEMPORAL_NAMESPACE
               value: cloud
+            {{- range $k, $v := .Values.extraEnv }}
+            {{- if has $k (list "CONFIG_FILE_PATH" "TEMPORAL_NAMESPACE") }}
+            {{- fail (printf "extraEnv must not override chart-managed variable %s" $k) }}
+            {{- end }}
+            - name: {{ $k }}
+              value: {{ $v | quote }}
+            {{- end }}
             - name: TEMPORAL_QUEUE
               value: cloud
           volumeMounts:
diff --git a/helm/rest/nico-rest/charts/nico-rest-workflow/templates/deployment-site-worker.yaml b/helm/rest/nico-rest/charts/nico-rest-workflow/templates/deployment-site-worker.yaml
index cadd38f725..08746dbe05 100644
--- a/helm/rest/nico-rest/charts/nico-rest-workflow/templates/deployment-site-worker.yaml
+++ b/helm/rest/nico-rest/charts/nico-rest-workflow/templates/deployment-site-worker.yaml
@@ -44,6 +44,13 @@ spec:
               value: /app/config.yaml
             - name: TEMPORAL_NAMESPACE
               value: site
+            {{- range $k, $v := .Values.extraEnv }}
+            {{- if has $k (list "CONFIG_FILE_PATH" "TEMPORAL_NAMESPACE") }}
+            {{- fail (printf "extraEnv must not override chart-managed variable %s" $k) }}
+            {{- end }}
+            - name: {{ $k }}
+              value: {{ $v | quote }}
+            {{- end }}
             - name: TEMPORAL_QUEUE
               value: site
           volumeMounts:
diff --git a/helm/rest/nico-rest/charts/nico-rest-workflow/values.yaml b/helm/rest/nico-rest/charts/nico-rest-workflow/values.yaml
index dd7b1de0ed..dbae93b9e0 100644
--- a/helm/rest/nico-rest/charts/nico-rest-workflow/values.yaml
+++ b/helm/rest/nico-rest/charts/nico-rest-workflow/values.yaml
@@ -82,3 +82,6 @@ config:
   tracing:
     enabled: false
     serviceName: nico-rest-workflow
+
+# -- Extra container environment, name->value. Mainly for OTEL_* variables.
+extraEnv: {}
diff --git a/rest-api/api/cmd/api/main.go b/rest-api/api/cmd/api/main.go
index a91dc69c87..88f80b3398 100644
--- a/rest-api/api/cmd/api/main.go
+++ b/rest-api/api/cmd/api/main.go
@@ -20,6 +20,8 @@ import (
 
 	// Imports for API doc generation
 	_ "github.com/NVIDIA/infra-controller/rest-api/api/pkg/api/model"
+
+	"github.com/NVIDIA/infra-controller/rest-api/common/pkg/tracing"
 )
 
 const (
@@ -43,6 +45,10 @@ const (
 // @in header
 // @name Authorization
 func main() {
+	// First: interceptors and handlers below capture the global propagator.
+	tracing.InstallPropagator()
+	// No-op unless OTEL_EXPORTER_OTLP_ENDPOINT is set.
+	defer tracing.InstallExporter("nico-rest-api")()
 	// Initialize logger
 	zerolog.TimeFieldFormat = zerolog.TimeFormatUnix
 	zerolog.LevelFieldName = ZerologLevelFieldName
diff --git a/rest-api/api/internal/server/server.go b/rest-api/api/internal/server/server.go
index 862abeaca1..15d36d14ba 100644
--- a/rest-api/api/internal/server/server.go
+++ b/rest-api/api/internal/server/server.go
@@ -40,6 +40,7 @@ import (
 	authn "github.com/NVIDIA/infra-controller/rest-api/auth/pkg/authentication"
 	otprop "go.opentelemetry.io/contrib/propagators/ot"
 	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/propagation"
 	"go.temporal.io/sdk/contrib/opentelemetry"
 	"go.temporal.io/sdk/interceptor"
 	"golang.org/x/time/rate"
@@ -190,7 +191,15 @@ func InitAPIServer(cfg *config.Config, dbSession *cdb.Session, tc tsdkClient.Cli
 	if cfg.GetTracingEnabled() {
 		svcName := cfg.GetTracingServiceName()
 		if svcName != "" {
-			e.Use(otelecho.Middleware(svcName, otelecho.WithSkipper(skipTracingRoutes), otelecho.WithPropagators(otprop.OT{})))
+			// Composite: WithPropagators replaces, so OT alone dropped W3C.
+			e.Use(otelecho.Middleware(svcName,
+				otelecho.WithSkipper(skipTracingRoutes),
+				otelecho.WithPropagators(propagation.NewCompositeTextMapPropagator(
+					propagation.TraceContext{},
+					propagation.Baggage{},
+					otprop.OT{},
+				)),
+			))
 		} else {
 			log.Warn().Msg("failed to get Tracing Service Name, skipping OTel middleware")
 		}
diff --git a/rest-api/api/pkg/client/site/temporal.go b/rest-api/api/pkg/client/site/temporal.go
index cea2421a46..199a104817 100644
--- a/rest-api/api/pkg/client/site/temporal.go
+++ b/rest-api/api/pkg/client/site/temporal.go
@@ -16,8 +16,11 @@ import (
 	zlogadapter "logur.dev/adapter/zerolog"
 	"logur.dev/logur"
 
+	"go.opentelemetry.io/otel"
 	tsdkClient "go.temporal.io/sdk/client"
+	"go.temporal.io/sdk/contrib/opentelemetry"
 	tsdkConverter "go.temporal.io/sdk/converter"
+	"go.temporal.io/sdk/interceptor"
 
 	cconfig "github.com/NVIDIA/infra-controller/rest-api/common/pkg/config"
 )
@@ -56,6 +59,15 @@ func (cp *ClientPool) GetClientByID(siteID uuid.UUID) (tsdkClient.Client, error)
 
 	tLogger := logur.LoggerToKV(zlogadapter.New(zerolog.New(os.Stderr)))
 
+	// Every SiteTaskQueue workflow leaves through this client.
+	var tInterceptors []interceptor.ClientInterceptor
+	otelInterceptor, oerr := opentelemetry.NewTracingInterceptor(
+		opentelemetry.TracerOptions{TextMapPropagator: otel.GetTextMapPropagator()})
+	if oerr != nil {
+		return nil, fmt.Errorf("creating Temporal tracing interceptor: %w", oerr)
+	}
+	tInterceptors = append(tInterceptors, otelInterceptor)
+
 	tc, err := tsdkClient.NewLazyClient(tsdkClient.Options{
 		HostPort:  fmt.Sprintf("%v:%v", cp.tcfg.Host, cp.tcfg.Port),
 		Namespace: siteID.String(),
@@ -71,7 +83,8 @@ func (cp *ClientPool) GetClientByID(siteID uuid.UUID) (tsdkClient.Client, error)
 			tsdkConverter.NewProtoPayloadConverter(),
 			tsdkConverter.NewJSONPayloadConverter(),
 		),
-		Logger: tLogger,
+		Logger:       tLogger,
+		Interceptors: tInterceptors,
 	})
 
 	if err != nil {
diff --git a/rest-api/common/pkg/tracing/propagator.go b/rest-api/common/pkg/tracing/propagator.go
new file mode 100644
index 0000000000..fdc077a600
--- /dev/null
+++ b/rest-api/common/pkg/tracing/propagator.go
@@ -0,0 +1,19 @@
+// SPDX-FileCopyrightText: Copyright (c) 2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+// Package tracing installs the process-wide OpenTelemetry propagator and exporter.
+package tracing
+
+import (
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/propagation"
+)
+
+// InstallPropagator sets the global text-map propagator to W3C trace context
+// plus baggage. Call it first in main, before anything captures the global.
+func InstallPropagator() {
+	otel.SetTextMapPropagator(propagation.NewCompositeTextMapPropagator(
+		propagation.TraceContext{},
+		propagation.Baggage{},
+	))
+}
diff --git a/rest-api/common/pkg/tracing/provider.go b/rest-api/common/pkg/tracing/provider.go
new file mode 100644
index 0000000000..30062dd2e9
--- /dev/null
+++ b/rest-api/common/pkg/tracing/provider.go
@@ -0,0 +1,54 @@
+// SPDX-FileCopyrightText: Copyright (c) 2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package tracing
+
+import (
+	"context"
+	"fmt"
+	"os"
+
+	"github.com/rs/zerolog/log"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc"
+	"go.opentelemetry.io/otel/sdk/resource"
+	sdktrace "go.opentelemetry.io/otel/sdk/trace"
+)
+
+// InstallTracerProvider installs an OTLP exporter, or a no-op when
+// OTEL_EXPORTER_OTLP_ENDPOINT is unset. Returns its shutdown func.
+func InstallTracerProvider(ctx context.Context, serviceName string) (func(context.Context) error, error) {
+	noop := func(context.Context) error { return nil }
+	if os.Getenv("OTEL_EXPORTER_OTLP_ENDPOINT") == "" &&
+		os.Getenv("OTEL_EXPORTER_OTLP_TRACES_ENDPOINT") == "" {
+		return noop, nil
+	}
+
+	exp, err := otlptracegrpc.New(ctx)
+	if err != nil {
+		return noop, fmt.Errorf("creating OTLP trace exporter: %w", err)
+	}
+
+	res, err := resource.Merge(resource.Default(),
+		resource.NewWithAttributes(resource.Default().SchemaURL(),
+			attribute.String("service.name", serviceName)))
+	if err != nil {
+		return noop, fmt.Errorf("building trace resource for %s: %w", serviceName, err)
+	}
+
+	tp := sdktrace.NewTracerProvider(sdktrace.WithBatcher(exp), sdktrace.WithResource(res))
+	otel.SetTracerProvider(tp)
+	return tp.Shutdown, nil
+}
+
+// InstallExporter is InstallTracerProvider for a main(): one line, errors logged.
+func InstallExporter(serviceName string) func() {
+	shutdown, err := InstallTracerProvider(context.Background(), serviceName)
+	if err != nil {
+		log.Warn().Err(err).Str("service", serviceName).
+			Msg("tracing: no TracerProvider installed; spans will not be exported")
+		return func() {}
+	}
+	return func() { _ = shutdown(context.Background()) }
+}
diff --git a/rest-api/docker/local/Dockerfile.nico-rest-site-manager b/rest-api/docker/local/Dockerfile.nico-rest-site-manager
index 30de710c74..62206687c3 100644
--- a/rest-api/docker/local/Dockerfile.nico-rest-site-manager
+++ b/rest-api/docker/local/Dockerfile.nico-rest-site-manager
@@ -34,6 +34,7 @@ RUN go mod download
 # Copy source files
 COPY site-manager/ ./site-manager/
 COPY cert-manager/ ./cert-manager/
+COPY common/ ./common/
 
 # Build the site manager
 WORKDIR /workspace/site-manager
diff --git a/rest-api/docker/production/Dockerfile.nico-rest-site-manager b/rest-api/docker/production/Dockerfile.nico-rest-site-manager
index 42a04f1d9f..0b66715f20 100644
--- a/rest-api/docker/production/Dockerfile.nico-rest-site-manager
+++ b/rest-api/docker/production/Dockerfile.nico-rest-site-manager
@@ -32,6 +32,9 @@ RUN go mod download
 # Copy source files
 COPY site-manager/ ./site-manager/
 COPY cert-manager/ ./cert-manager/
+# common/pkg/tracing installs the global propagator; every other rest-api
+# image already copies common/ for it.
+COPY common/ ./common/
 
 # Build the site manager
 WORKDIR /workspace/site-manager
diff --git a/rest-api/flow/main.go b/rest-api/flow/main.go
index ee9f96c3d8..ba1b6d195c 100644
--- a/rest-api/flow/main.go
+++ b/rest-api/flow/main.go
@@ -3,8 +3,16 @@
 
 package main
 
-import "github.com/NVIDIA/infra-controller/rest-api/flow/cmd"
+import (
+	"github.com/NVIDIA/infra-controller/rest-api/flow/cmd"
+
+	"github.com/NVIDIA/infra-controller/rest-api/common/pkg/tracing"
+)
 
 func main() {
+	// First: interceptors and handlers below capture the global propagator.
+	tracing.InstallPropagator()
+	// No-op unless OTEL_EXPORTER_OTLP_ENDPOINT is set.
+	defer tracing.InstallExporter("flow")()
 	cmd.Execute()
 }
diff --git a/rest-api/go.mod b/rest-api/go.mod
index 4166bcd2fa..fea142dab0 100644
--- a/rest-api/go.mod
+++ b/rest-api/go.mod
@@ -15,8 +15,8 @@ require (
 	github.com/Nerzal/gocloak/v13 v13.9.0
 	github.com/PagerDuty/go-pagerduty v1.8.0
 	github.com/avast/retry-go/v4 v4.7.0
-	github.com/creack/pty v1.1.24
 	github.com/bufbuild/buf v1.72.0
+	github.com/creack/pty v1.1.24
 	github.com/deckarep/golang-set/v2 v2.8.0
 	github.com/felixge/httpsnoop v1.1.0
 	github.com/fsnotify/fsnotify v1.9.0
@@ -175,6 +175,7 @@ require (
 	github.com/catenacyber/perfsprint v0.10.1 // indirect
 	github.com/ccojocar/zxcvbn-go v1.0.4 // indirect
 	github.com/cenkalti/backoff/v4 v4.3.0 // indirect
+	github.com/cenkalti/backoff/v5 v5.0.3 // indirect
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/charithe/durationcheck v0.0.11 // indirect
 	github.com/charmbracelet/colorprofile v0.4.3 // indirect
@@ -434,7 +435,10 @@ require (
 	go.lsp.dev/protocol v0.12.0 // indirect
 	go.lsp.dev/uri v0.3.0 // indirect
 	go.opentelemetry.io/auto/sdk v1.2.1 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.38.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.38.0 // indirect
 	go.opentelemetry.io/otel/metric v1.44.0 // indirect
+	go.opentelemetry.io/proto/otlp v1.7.1 // indirect
 	go.uber.org/mock v0.6.0 // indirect
 	go.uber.org/multierr v1.11.0 // indirect
 	go.uber.org/zap v1.28.0 // indirect
diff --git a/rest-api/go.sum b/rest-api/go.sum
index 1640361701..2c623f3b28 100644
--- a/rest-api/go.sum
+++ b/rest-api/go.sum
@@ -163,6 +163,8 @@ github.com/ccojocar/zxcvbn-go v1.0.4 h1:FWnCIRMXPj43ukfX000kvBZvV6raSxakYr1nzyNr
 github.com/ccojocar/zxcvbn-go v1.0.4/go.mod h1:3GxGX+rHmueTUMvm5ium7irpyjmm7ikxYFOSJB21Das=
 github.com/cenkalti/backoff/v4 v4.3.0 h1:MyRJ/UdXutAwSAT+s3wNd7MfTIcy71VQueUuFK343L8=
 github.com/cenkalti/backoff/v4 v4.3.0/go.mod h1:Y3VNntkOUPxTVeUxJ/G5vcM//AlwfmyYozVcomhLiZE=
+github.com/cenkalti/backoff/v5 v5.0.3 h1:ZN+IMa753KfX5hd8vVaMixjnqRZ3y8CuJKRKj1xcsSM=
+github.com/cenkalti/backoff/v5 v5.0.3/go.mod h1:rkhZdG3JZukswDf7f0cwqPNk4K0sa+F97BxZthm/crw=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
 github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
 github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
@@ -948,6 +950,10 @@ go.opentelemetry.io/contrib/propagators/ot v1.39.0 h1:vKTve1W/WKPVp1fzJamhCDDECt
 go.opentelemetry.io/contrib/propagators/ot v1.39.0/go.mod h1:FH5VB2N19duNzh1Q8ks6CsZFyu3LFhNLiA9lPxyEkvU=
 go.opentelemetry.io/otel v1.44.0 h1:JjwHmHpA4iZ3wBxluu2fbbE7j4kqlE8jXyAyPXH7HqU=
 go.opentelemetry.io/otel v1.44.0/go.mod h1:BMgjTHL9WPRlRjL2oZCBTL4whCGtXch2H4BhOPIAyYc=
+go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.38.0 h1:GqRJVj7UmLjCVyVJ3ZFLdPRmhDUp2zFmQe3RHIOsw24=
+go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.38.0/go.mod h1:ri3aaHSmCTVYu2AWv44YMauwAQc0aqI9gHKIcSbI1pU=
+go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.38.0 h1:lwI4Dc5leUqENgGuQImwLo4WnuXFPetmPpkLi2IrX54=
+go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.38.0/go.mod h1:Kz/oCE7z5wuyhPxsXDuaPteSWqjSBD5YaSdbxZYGbGk=
 go.opentelemetry.io/otel/exporters/prometheus v0.66.0 h1:vkrK8PAznv2NKt2r+kdu252ccGzkEqLc2aSXbQIALYQ=
 go.opentelemetry.io/otel/exporters/prometheus v0.66.0/go.mod h1:V/UB6D3vMF/UBOL5igAsAYnk1nG/bzYYTzvsB16cy7o=
 go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.39.0 h1:8UPA4IbVZxpsD76ihGOQiFml99GPAEZLohDXvqHdi6U=
@@ -962,6 +968,8 @@ go.opentelemetry.io/otel/sdk/metric v1.44.0 h1:3LlKgI+VjbVsjNRFZJZAJ30WjXC5VkNRk
 go.opentelemetry.io/otel/sdk/metric v1.44.0/go.mod h1:5B5pMARnXxKhltooO4xUuCBorl65a4EpnTalObqOigA=
 go.opentelemetry.io/otel/trace v1.44.0 h1:jxF5CsGYCe74MCRx2X4g7WsY/VBKRqqpNvXlX/6gtIk=
 go.opentelemetry.io/otel/trace v1.44.0/go.mod h1:oLl1jrMQAVo6v3GAggN+1VH9VIz9iUSvW53sW1Q8PIE=
+go.opentelemetry.io/proto/otlp v1.7.1 h1:gTOMpGDb0WTBOP8JaO72iL3auEZhVmAQg4ipjOVAtj4=
+go.opentelemetry.io/proto/otlp v1.7.1/go.mod h1:b2rVh6rfI/s2pHWNlB7ILJcRALpcNDzKhACevjI+ZnE=
 go.temporal.io/api v1.60.0 h1:SlRkizt3PXu/J62NWlUNLldHtJhUxfsBRuF4T0KYkgY=
 go.temporal.io/api v1.60.0/go.mod h1:iaxoP/9OXMJcQkETTECfwYq4cw/bj4nwov8b3ZLVnXM=
 go.temporal.io/sdk v1.39.0 h1:+rtLK8BtT+0+b0DiSdgeQIFkONrLIUqjNfiIxMPF8VA=
diff --git a/rest-api/site-agent/cmd/site-agent/main.go b/rest-api/site-agent/cmd/site-agent/main.go
index be281db558..6fa0c1f737 100644
--- a/rest-api/site-agent/cmd/site-agent/main.go
+++ b/rest-api/site-agent/cmd/site-agent/main.go
@@ -13,6 +13,8 @@ import (
 	components "github.com/NVIDIA/infra-controller/rest-api/site-agent/pkg/components"
 	"github.com/NVIDIA/infra-controller/rest-api/site-agent/pkg/datatypes/elektratypes"
 	"github.com/rs/zerolog/log"
+
+	"github.com/NVIDIA/infra-controller/rest-api/common/pkg/tracing"
 )
 
 // InitElektra initializes the Elektra site agent framework
@@ -42,6 +44,10 @@ func InitElektra() {
 }
 
 func main() {
+	// First: interceptors and handlers below capture the global propagator.
+	tracing.InstallPropagator()
+	// No-op unless OTEL_EXPORTER_OTLP_ENDPOINT is set.
+	defer tracing.InstallExporter("site-agent")()
 	InitElektra()
 	// sleep
 	// Wait forever
diff --git a/rest-api/site-agent/pkg/components/managers/workflow/orchestrator.go b/rest-api/site-agent/pkg/components/managers/workflow/orchestrator.go
index 66a19c1d6f..a91c9d1930 100644
--- a/rest-api/site-agent/pkg/components/managers/workflow/orchestrator.go
+++ b/rest-api/site-agent/pkg/components/managers/workflow/orchestrator.go
@@ -15,7 +15,9 @@ import (
 	zlogadapter "logur.dev/adapter/zerolog"
 	"logur.dev/logur"
 
+	"go.opentelemetry.io/otel"
 	"go.temporal.io/sdk/client"
+	"go.temporal.io/sdk/contrib/opentelemetry"
 	"go.temporal.io/sdk/interceptor"
 	"go.temporal.io/sdk/worker"
 
@@ -71,6 +73,15 @@ func workflowOrchestrator() error {
 	var clientInterceptors []interceptor.ClientInterceptor
 	var workerInterceptors []interceptor.WorkerInterceptor
 
+	// otelErr, not err: `var err error` is declared further down.
+	otelInterceptor, otelErr := opentelemetry.NewTracingInterceptor(
+		opentelemetry.TracerOptions{TextMapPropagator: otel.GetTextMapPropagator()})
+	if otelErr != nil {
+		return fmt.Errorf("creating Temporal tracing interceptor: %w", otelErr)
+	}
+	clientInterceptors = append(clientInterceptors, otelInterceptor)
+	workerInterceptors = append(workerInterceptors, otelInterceptor)
+
 	// Create logger for temporal using
 	// zero logger
 	// This is optional
diff --git a/rest-api/site-manager/cmd/sitemgr/main.go b/rest-api/site-manager/cmd/sitemgr/main.go
index 5f9ea721f0..c14465461d 100644
--- a/rest-api/site-manager/cmd/sitemgr/main.go
+++ b/rest-api/site-manager/cmd/sitemgr/main.go
@@ -11,9 +11,15 @@ import (
 	"github.com/NVIDIA/infra-controller/rest-api/cert-manager/pkg/core"
 	"github.com/NVIDIA/infra-controller/rest-api/site-manager/pkg/sitemgr"
 	cli "github.com/urfave/cli/v2"
+
+	"github.com/NVIDIA/infra-controller/rest-api/common/pkg/tracing"
 )
 
 func main() {
+	// First: interceptors and handlers below capture the global propagator.
+	tracing.InstallPropagator()
+	// No-op unless OTEL_EXPORTER_OTLP_ENDPOINT is set.
+	defer tracing.InstallExporter("site-manager")()
 	cmd := sitemgr.NewCommand()
 	app := &cli.App{
 		Name:    cmd.Name,
diff --git a/rest-api/site-workflow/pkg/grpc/client/core_client.go b/rest-api/site-workflow/pkg/grpc/client/core_client.go
index e18382fb09..caf3880000 100644
--- a/rest-api/site-workflow/pkg/grpc/client/core_client.go
+++ b/rest-api/site-workflow/pkg/grpc/client/core_client.go
@@ -190,10 +190,9 @@ func NewCoreGrpcClient(config *CoreGrpcClientConfig) (client *CoreGrpcClient, er
 	if config.ClientMetrics != nil {
 		streamInterceptors = append(streamInterceptors, newGrpcStreamMetricsInterceptor(config.ClientMetrics))
 	}
-	if os.Getenv("LS_SERVICE_NAME") != "" {
-		handler := otelgrpc.NewClientHandler(otelgrpc.WithPropagators(otel.GetTextMapPropagator()))
-		client.dialOpts = append(client.dialOpts, grpc.WithStatsHandler(handler))
-	}
+	// Unconditional: was gated on LS_SERVICE_NAME, which no chart sets.
+	handler := otelgrpc.NewClientHandler(otelgrpc.WithPropagators(otel.GetTextMapPropagator()))
+	client.dialOpts = append(client.dialOpts, grpc.WithStatsHandler(handler))
 	if len(unaryInterceptors) > 0 {
 		client.dialOpts = append(client.dialOpts, grpc.WithUnaryInterceptor(grpcmw.ChainUnaryClient(unaryInterceptors...)))
 	}
diff --git a/rest-api/site-workflow/pkg/grpc/client/flow_client.go b/rest-api/site-workflow/pkg/grpc/client/flow_client.go
index 837d0eac23..30e60bab61 100644
--- a/rest-api/site-workflow/pkg/grpc/client/flow_client.go
+++ b/rest-api/site-workflow/pkg/grpc/client/flow_client.go
@@ -191,10 +191,9 @@ func NewFlowGrpcClient(config *FlowGrpcClientConfig) (client *FlowGrpcClient, er
 	if config.ClientMetrics != nil {
 		streamInterceptors = append(streamInterceptors, newGrpcStreamMetricsInterceptor(config.ClientMetrics))
 	}
-	if os.Getenv("LS_SERVICE_NAME") != "" {
-		handler := otelgrpc.NewClientHandler(otelgrpc.WithPropagators(otel.GetTextMapPropagator()))
-		client.dialOpts = append(client.dialOpts, grpc.WithStatsHandler(handler))
-	}
+	// Unconditional: was gated on LS_SERVICE_NAME, which no chart sets.
+	handler := otelgrpc.NewClientHandler(otelgrpc.WithPropagators(otel.GetTextMapPropagator()))
+	client.dialOpts = append(client.dialOpts, grpc.WithStatsHandler(handler))
 	if len(unaryInterceptors) > 0 {
 		client.dialOpts = append(client.dialOpts, grpc.WithUnaryInterceptor(grpcmw.ChainUnaryClient(unaryInterceptors...)))
 	}
diff --git a/rest-api/workflow/cmd/workflow/main.go b/rest-api/workflow/cmd/workflow/main.go
index 447fa471db..1cf0f33cf5 100644
--- a/rest-api/workflow/cmd/workflow/main.go
+++ b/rest-api/workflow/cmd/workflow/main.go
@@ -104,6 +104,8 @@ import (
 
 	nvLinkLogicalPartitionActivity "github.com/NVIDIA/infra-controller/rest-api/workflow/pkg/activity/nvlinklogicalpartition"
 	nvLinkLogicalPartitionWorkflow "github.com/NVIDIA/infra-controller/rest-api/workflow/pkg/workflow/nvlinklogicalpartition"
+
+	"github.com/NVIDIA/infra-controller/rest-api/common/pkg/tracing"
 )
 
 const (
@@ -114,6 +116,10 @@ const (
 )
 
 func main() {
+	// First: interceptors and handlers below capture the global propagator.
+	tracing.InstallPropagator()
+	// No-op unless OTEL_EXPORTER_OTLP_ENDPOINT is set.
+	defer tracing.InstallExporter("nico-rest-workflow")()
 	// Initialize context
 	ctx := context.Background()
 
@@ -188,6 +194,7 @@ func main() {
 	}
 
 	var tInterceptors []interceptor.ClientInterceptor
+	var wInterceptors []interceptor.WorkerInterceptor
 
 	if cfg.GetTracingEnabled() {
 		otelInterceptor, err := opentelemetry.NewTracingInterceptor(opentelemetry.TracerOptions{TextMapPropagator: otel.GetTextMapPropagator()})
@@ -195,6 +202,7 @@ func main() {
 			log.Panic().Err(err).Msg("unable to get otelInterceptor")
 		}
 		tInterceptors = append(tInterceptors, otelInterceptor)
+		wInterceptors = append(wInterceptors, otelInterceptor)
 	}
 
 	tc, err = tsdkClient.NewLazyClient(tsdkClient.Options{
@@ -212,8 +220,8 @@ func main() {
 			tsdkConverter.NewProtoPayloadConverter(),
 			tsdkConverter.NewJSONPayloadConverter(),
 		),
-		// Interceptors: tInterceptors,
-		Logger: tLogger,
+		Interceptors: tInterceptors,
+		Logger:       tLogger,
 	})
 
 	if err != nil {
@@ -226,6 +234,7 @@ func main() {
 		WorkflowPanicPolicy:              tsdkWorker.FailWorkflow,
 		MaxConcurrentActivityTaskPollers: 10,
 		MaxConcurrentWorkflowTaskPollers: 10,
+		Interceptors:                     wInterceptors,
 	})
 
 	siteClientPool := sc.NewClientPool(tcfg)
diff --git a/rest-api/workflow/pkg/client/site/temporal.go b/rest-api/workflow/pkg/client/site/temporal.go
index 2351cb13f2..4b326184a9 100644
--- a/rest-api/workflow/pkg/client/site/temporal.go
+++ b/rest-api/workflow/pkg/client/site/temporal.go
@@ -16,8 +16,11 @@ import (
 	zlogadapter "logur.dev/adapter/zerolog"
 	"logur.dev/logur"
 
+	"go.opentelemetry.io/otel"
 	tsdkClient "go.temporal.io/sdk/client"
+	"go.temporal.io/sdk/contrib/opentelemetry"
 	tsdkConverter "go.temporal.io/sdk/converter"
+	"go.temporal.io/sdk/interceptor"
 
 	cconfig "github.com/NVIDIA/infra-controller/rest-api/common/pkg/config"
 )
@@ -45,6 +48,15 @@ func (cp *ClientPool) GetClientByID(siteID uuid.UUID) (tsdkClient.Client, error)
 
 	tLogger := logur.LoggerToKV(zlogadapter.New(zerolog.New(os.Stderr)))
 
+	// Every SiteTaskQueue workflow leaves through this client.
+	var tInterceptors []interceptor.ClientInterceptor
+	otelInterceptor, oerr := opentelemetry.NewTracingInterceptor(
+		opentelemetry.TracerOptions{TextMapPropagator: otel.GetTextMapPropagator()})
+	if oerr != nil {
+		return nil, fmt.Errorf("creating Temporal tracing interceptor: %w", oerr)
+	}
+	tInterceptors = append(tInterceptors, otelInterceptor)
+
 	tc, err := tsdkClient.NewLazyClient(tsdkClient.Options{
 		HostPort:  fmt.Sprintf("%v:%v", cp.tcfg.Host, cp.tcfg.Port),
 		Namespace: siteID.String(),
@@ -60,7 +72,8 @@ func (cp *ClientPool) GetClientByID(siteID uuid.UUID) (tsdkClient.Client, error)
 			tsdkConverter.NewProtoPayloadConverter(),
 			tsdkConverter.NewJSONPayloadConverter(),
 		),
-		Logger: tLogger,
+		Logger:       tLogger,
+		Interceptors: tInterceptors,
 	})
 
 	if err != nil {