diff --git a/src/main/java/djmil/cashcard/CashCardController.java b/src/main/java/djmil/cashcard/CashCardController.java
index 011f697..6787d20 100644
--- a/src/main/java/djmil/cashcard/CashCardController.java
+++ b/src/main/java/djmil/cashcard/CashCardController.java
@@ -13,6 +13,8 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.util.UriComponentsBuilder;
 
+import java.security.Principal;
+
 import java.net.URI;
 import java.util.List;
 import java.util.Optional;
@@ -28,8 +30,12 @@ public class CashCardController {
     }
 
     @GetMapping("/{requestedId}")
-    public ResponseEntity<CashCard> findById(@PathVariable Long requestedId) {
-        Optional<CashCard> cashCardOptional = cashCardRepository.findById(requestedId);
+    public ResponseEntity<CashCard> findById(@PathVariable Long requestedId, Principal principal) {
+        CashCard cashCard = cashCardRepository.findByIdAndOwner(
+	            requestedId, 
+	            principal.getName()
+        );
+        Optional<CashCard> cashCardOptional = Optional.ofNullable(cashCard);
 
         if (cashCardOptional.isPresent()) {
             return ResponseEntity.ok(cashCardOptional.get());
@@ -44,8 +50,9 @@ public class CashCardController {
     // }
 
     @GetMapping
-    public ResponseEntity<List<CashCard>> findAll(Pageable pageable) {
-        Page<CashCard> page = cashCardRepository.findAll(
+    public ResponseEntity<List<CashCard>> findAll(Pageable pageable, Principal principal) {
+        Page<CashCard> page = cashCardRepository.findByOwner(
+                principal.getName(),
                 PageRequest.of(
                         pageable.getPageNumber(),
                         pageable.getPageSize(),
@@ -56,13 +63,15 @@ public class CashCardController {
     }
 
     @PostMapping
-    private ResponseEntity<Void> createCashCard(@RequestBody CashCard newCashCardRequest, UriComponentsBuilder ucb) {
-        CashCard savedCashCard = cashCardRepository.save(newCashCardRequest); // CRUD - Create
+    private ResponseEntity<Void> createCashCard(@RequestBody CashCard newCashCardRequest, UriComponentsBuilder ucb, Principal principal) {
+        CashCard cashCardWithOwner = new CashCard(null, newCashCardRequest.amount(), principal.getName());
+        CashCard savedCashCard = cashCardRepository.save(cashCardWithOwner); // CRUD - Create
 
         URI locationOfNewCashCard = ucb
                 .path("cashcards/{id}")
                 .buildAndExpand(savedCashCard.id())
                 .toUri();
+
         return ResponseEntity.created(locationOfNewCashCard).build();
     }
 }
diff --git a/src/main/java/djmil/cashcard/CashCardRepository.java b/src/main/java/djmil/cashcard/CashCardRepository.java
index 9818157..8e5e602 100644
--- a/src/main/java/djmil/cashcard/CashCardRepository.java
+++ b/src/main/java/djmil/cashcard/CashCardRepository.java
@@ -2,10 +2,15 @@ package djmil.cashcard;
 
 import org.springframework.data.repository.CrudRepository;
 import org.springframework.data.repository.PagingAndSortingRepository;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.PageRequest;
 
 public interface 
     CashCardRepository 
 extends 
     CrudRepository<CashCard, Long>, 
-    PagingAndSortingRepository<CashCard, Long> {
+    PagingAndSortingRepository<CashCard, Long>     
+{
+    CashCard findByIdAndOwner(Long id, String owner);
+	Page<CashCard> findByOwner(String owner, PageRequest amount);
 }
diff --git a/src/test/java/djmil/cashcard/CashcardApplicationTests.java b/src/test/java/djmil/cashcard/CashcardApplicationTests.java
index a17ef59..a287d48 100644
--- a/src/test/java/djmil/cashcard/CashcardApplicationTests.java
+++ b/src/test/java/djmil/cashcard/CashcardApplicationTests.java
@@ -59,7 +59,7 @@ class CashcardApplicationTests {
 	@Test
 	@DirtiesContext
 	void shouldCreateANewCashCard() {
-		CashCard newCashCard = new CashCard(null, 250.00, "sarah1");
+		CashCard newCashCard = new CashCard(null, 250.00, null);
 		ResponseEntity<Void> createResponse = restTemplate
 			.withBasicAuth("sarah1", "abc123")
 			.postForEntity("/cashcards", newCashCard, Void.class );
@@ -161,4 +161,12 @@ class CashcardApplicationTests {
 		.getForEntity("/cashcards/99", String.class);
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.FORBIDDEN);
 	}
+
+	@Test
+	void shouldNotAllowAccessToCashCardsTheyDoNotOwn() {
+		ResponseEntity<String> response = restTemplate
+		.withBasicAuth("sarah1", "abc123")
+		.getForEntity("/cashcards/102", String.class); // <<-- kumar2's data
+		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.NOT_FOUND);
+	}
 }
diff --git a/src/test/resources/data.sql b/src/test/resources/data.sql
index 2134f06..f1ab8ff 100644
--- a/src/test/resources/data.sql
+++ b/src/test/resources/data.sql
@@ -1,3 +1,4 @@
 INSERT INTO CASH_CARD(ID, AMOUNT, OWNER) VALUES (99, 123.45, 'sarah1');
 INSERT INTO CASH_CARD(ID, AMOUNT, OWNER) VALUES (100, 1.00, 'sarah1');
-INSERT INTO CASH_CARD(ID, AMOUNT, OWNER) VALUES (101, 150.00, 'sarah1');
\ No newline at end of file
+INSERT INTO CASH_CARD(ID, AMOUNT, OWNER) VALUES (101, 150.00, 'sarah1');
+INSERT INTO CASH_CARD(ID, AMOUNT, OWNER) VALUES (102, 200.00, 'kumar2');
\ No newline at end of file