diff --git a/dongle-smartcontract/src/tests/endorsements.rs b/dongle-smartcontract/src/tests/endorsements.rs
index f62d46d4..e39a0090 100644
--- a/dongle-smartcontract/src/tests/endorsements.rs
+++ b/dongle-smartcontract/src/tests/endorsements.rs
@@ -5,7 +5,18 @@ use crate::ContractError;
 use soroban_sdk::{testutils::Address as _, Address, Env};
 
 #[test]
-fn test_endorse_project() {
+fn endorsement_defaults_are_empty() {
+    let env = Env::default();
+
+    let (client, _admin) = setup_contract(&env);
+    let user = Address::generate(&env);
+
+    assert_eq!(client.get_endorsement_count(&999), 0);
+    assert!(!client.has_endorsed(&999, &user));
+}
+
+#[test]
+fn endorse_project_updates_count_and_membership() {
     let env = Env::default();
     env.mock_all_auths();
 
@@ -17,15 +28,12 @@ fn test_endorse_project() {
 
     client.endorse_project(&project_id, &user);
 
-    let count = client.get_endorsement_count(&project_id);
-    assert_eq!(count, 1);
-
-    let endorsed = client.has_endorsed(&project_id, &user);
-    assert!(endorsed);
+    assert_eq!(client.get_endorsement_count(&project_id), 1);
+    assert!(client.has_endorsed(&project_id, &user));
 }
 
 #[test]
-fn test_unendorse_project() {
+fn unendorse_project_updates_count_and_membership() {
     let env = Env::default();
     env.mock_all_auths();
 
@@ -41,12 +49,11 @@ fn test_unendorse_project() {
     client.unendorse_project(&project_id, &user);
     assert_eq!(client.get_endorsement_count(&project_id), 0);
 
-    let endorsed = client.has_endorsed(&project_id, &user);
-    assert!(!endorsed);
+    assert!(!client.has_endorsed(&project_id, &user));
 }
 
 #[test]
-fn test_duplicate_endorse_returns_error() {
+fn duplicate_endorse_returns_exact_error_without_changing_state() {
     let env = Env::default();
     env.mock_all_auths();
 
@@ -60,10 +67,12 @@ fn test_duplicate_endorse_returns_error() {
 
     let result = client.try_endorse_project(&project_id, &user);
     assert_eq!(result, Err(Ok(ContractError::AlreadyEndorsed)));
+    assert_eq!(client.get_endorsement_count(&project_id), 1);
+    assert!(client.has_endorsed(&project_id, &user));
 }
 
 #[test]
-fn test_endorse_nonexistent_project_returns_error() {
+fn endorse_nonexistent_project_returns_exact_error() {
     let env = Env::default();
     env.mock_all_auths();
 
@@ -75,7 +84,23 @@ fn test_endorse_nonexistent_project_returns_error() {
 }
 
 #[test]
-fn test_unendorse_without_endorsement_returns_error() {
+fn endorse_project_requires_user_authorization() {
+    let env = Env::default();
+
+    let (client, _admin) = setup_contract(&env);
+    let owner = Address::generate(&env);
+    let user = Address::generate(&env);
+    let project_id = create_test_project(&client, &owner, "UnauthorizedEndorseProject");
+
+    let result = client.try_endorse_project(&project_id, &user);
+
+    assert!(result.is_err());
+    assert_eq!(client.get_endorsement_count(&project_id), 0);
+    assert!(!client.has_endorsed(&project_id, &user));
+}
+
+#[test]
+fn unendorse_without_endorsement_returns_exact_error_without_changing_state() {
     let env = Env::default();
     env.mock_all_auths();
 
@@ -87,10 +112,49 @@ fn test_unendorse_without_endorsement_returns_error() {
 
     let result = client.try_unendorse_project(&project_id, &user);
     assert_eq!(result, Err(Ok(ContractError::NotEndorsed)));
+    assert_eq!(client.get_endorsement_count(&project_id), 0);
+    assert!(!client.has_endorsed(&project_id, &user));
+}
+
+#[test]
+fn unendorse_project_requires_user_authorization() {
+    let env = Env::default();
+
+    let (client, _admin) = setup_contract(&env);
+    let owner = Address::generate(&env);
+    let user = Address::generate(&env);
+    let project_id = create_test_project(&client, &owner, "UnauthorizedUnendorseProject");
+    client.mock_all_auths().endorse_project(&project_id, &user);
+
+    let result = client.try_unendorse_project(&project_id, &user);
+
+    assert!(result.is_err());
+    assert_eq!(client.get_endorsement_count(&project_id), 1);
+    assert!(client.has_endorsed(&project_id, &user));
 }
 
 #[test]
-fn test_endorse_count_multiple_users() {
+fn duplicate_unendorse_returns_exact_error_without_changing_state() {
+    let env = Env::default();
+    env.mock_all_auths();
+
+    let (client, _admin) = setup_contract(&env);
+    let owner = Address::generate(&env);
+    let user = Address::generate(&env);
+
+    let project_id = create_test_project(&client, &owner, "DoubleUnendorseProject");
+
+    client.endorse_project(&project_id, &user);
+    client.unendorse_project(&project_id, &user);
+
+    let result = client.try_unendorse_project(&project_id, &user);
+    assert_eq!(result, Err(Ok(ContractError::NotEndorsed)));
+    assert_eq!(client.get_endorsement_count(&project_id), 0);
+    assert!(!client.has_endorsed(&project_id, &user));
+}
+
+#[test]
+fn endorsement_count_tracks_multiple_users_and_partial_removal() {
     let env = Env::default();
     env.mock_all_auths();
 
@@ -99,21 +163,66 @@ fn test_endorse_count_multiple_users() {
 
     let project_id = create_test_project(&client, &owner, "MultiEndorseProject");
 
-    let user_count = 5u32;
-    for _ in 0..user_count {
-        let u = Address::generate(&env);
-        client.endorse_project(&project_id, &u);
-    }
-
-    assert_eq!(
-        client.get_endorsement_count(&project_id),
-        user_count,
-        "endorsement count should match total unique endorsers"
-    );
+    let first_user = Address::generate(&env);
+    let second_user = Address::generate(&env);
+    let third_user = Address::generate(&env);
+
+    client.endorse_project(&project_id, &first_user);
+    client.endorse_project(&project_id, &second_user);
+    client.endorse_project(&project_id, &third_user);
+
+    assert_eq!(client.get_endorsement_count(&project_id), 3);
+    assert!(client.has_endorsed(&project_id, &first_user));
+    assert!(client.has_endorsed(&project_id, &second_user));
+    assert!(client.has_endorsed(&project_id, &third_user));
+
+    client.unendorse_project(&project_id, &second_user);
+
+    assert_eq!(client.get_endorsement_count(&project_id), 2);
+    assert!(client.has_endorsed(&project_id, &first_user));
+    assert!(!client.has_endorsed(&project_id, &second_user));
+    assert!(client.has_endorsed(&project_id, &third_user));
+}
+
+#[test]
+fn endorsement_state_is_isolated_by_project_and_user() {
+    let env = Env::default();
+    env.mock_all_auths();
+
+    let (client, _admin) = setup_contract(&env);
+    let owner = Address::generate(&env);
+    let endorsing_user = Address::generate(&env);
+    let other_user = Address::generate(&env);
+
+    let first_project = create_test_project(&client, &owner, "FirstEndorsementProject");
+    let second_project = create_test_project(&client, &owner, "SecondEndorsementProject");
+
+    client.endorse_project(&first_project, &endorsing_user);
+
+    assert_eq!(client.get_endorsement_count(&first_project), 1);
+    assert_eq!(client.get_endorsement_count(&second_project), 0);
+    assert!(client.has_endorsed(&first_project, &endorsing_user));
+    assert!(!client.has_endorsed(&first_project, &other_user));
+    assert!(!client.has_endorsed(&second_project, &endorsing_user));
+}
+
+#[test]
+fn project_owner_can_self_endorse_under_current_policy() {
+    let env = Env::default();
+    env.mock_all_auths();
+
+    let (client, _admin) = setup_contract(&env);
+    let owner = Address::generate(&env);
+    let project_id = create_test_project(&client, &owner, "SelfEndorseProject");
+
+    client.endorse_project(&project_id, &owner);
+
+    assert_eq!(client.get_endorsement_count(&project_id), 1);
+    assert!(client.has_endorsed(&project_id, &owner));
 }
 
 #[test]
-fn test_endorse_after_unendorse_allows_reendorse() {
+fn endorse_after_unendorse_allows_reendorsement() {
     let env = Env::default();
     env.mock_all_auths();
 
@@ -130,6 +239,5 @@ fn test_endorse_after_unendorse_allows_reendorse() {
     client.endorse_project(&project_id, &user);
     assert_eq!(client.get_endorsement_count(&project_id), 1);
 
-    let endorsed = client.has_endorsed(&project_id, &user);
-    assert!(endorsed);
+    assert!(client.has_endorsed(&project_id, &user));
 }