diff --git a/src/database_components/table.rs b/src/database_components/table.rs
index 2ac3c30..b4dc6f8 100644
--- a/src/database_components/table.rs
+++ b/src/database_components/table.rs
@@ -71,6 +71,38 @@ impl Table {
             Err(format!("Row is missing an 'id' field: {:?}", row))
         }
     }
+
+     pub fn add_row_with_fk(
+        &mut self,
+        db: &Database,
+        row_data: serde_json::Value,
+        fk_constraints: Option<&[(&str, &str)]>, // Vec of (Table, Column)
+    ) -> Result<(), String> {
+        // Validate FK constraints if provided
+        if let Some(constraints) = fk_constraints {
+            for (table_name, fk_column) in constraints {
+                if let Some(fk_value) = row_data.get(fk_column).and_then(|v| v.as_str()) {
+                    if !db.record_exists(table_name, fk_value) {
+                        return Err(format!(
+                            "Foreign key constraint failed: `{}` does not exist in `{}`",
+                            fk_value, table_name
+                        ));
+                    }
+                } else {
+                    return Err(format!("Missing value for foreign key column `{}`", fk_column));
+                }
+            }
+        }
+
+        // Add the row after validation
+        let row_id = row_data
+            .get("id")
+            .and_then(|id| id.as_str())
+            .ok_or_else(|| "Missing primary key `id` in row data".to_string())?;
+
+        self.rows.insert(row_id.to_string(), Row::new(row_data));
+        Ok(())
+    }
 }
 
 #[cfg(test)]
diff --git a/src/database_operations/core.rs b/src/database_operations/core.rs
index e043839..2977f92 100644
--- a/src/database_operations/core.rs
+++ b/src/database_operations/core.rs
@@ -134,6 +134,14 @@ impl Database {
             )))
         }
     }
+
+    pub fn record_exists(&self, table_name: &str, pk_value: &str) -> bool {
+        if let Some(table) = self.tables.get(table_name) {
+            table.rows.contains_key(pk_value)
+        } else {
+            false
+        }
+    }
 }
 
 #[cfg(test)]
@@ -326,4 +334,65 @@ mod tests {
         let result = db.count_rows("NonExistentTable");
         assert!(matches!(result, Err(DatabaseError::TableNotFound(_))));
     }
+
+    #[tokio::test]
+    async fn test_foreign_key_validation() {
+        #[derive(Serialize, Deserialize, Debug, PartialEq, Clone, Default)]
+        struct Post {
+            id: String,
+            title: String,
+            content: String,
+            user_id: String,
+        }
+
+        #[derive(Serialize, Deserialize, Debug, PartialEq, Clone, Default)]
+        struct User {
+            id: String,
+            name: String,
+            email: String,
+        }
+
+        let mut db = setup_temp_db().await;
+
+        // Set up User table
+        let user_columns = Columns::from_struct::<User>(true);
+        let mut users_table = Table::new("users".to_string(), user_columns.clone());
+        db.add_table(&mut users_table).await.unwrap();
+
+        let user1 = json!({
+            "id": "1",
+            "name": "John Doe",
+            "email": "johndoe@example.com"
+        });
+        users_table.add_row(&mut db, user1).await;
+
+        // Set up Post table
+        let post_columns = Columns::from_struct::<Post>(true);
+        let mut posts_table = Table::new("posts".to_string(), post_columns.clone());
+        db.add_table(&mut posts_table).await.unwrap();
+
+        let valid_post = json!({
+            "id": "101",
+            "title": "Valid Post",
+            "content": "Content",
+            "user_id": "1"
+        });
+
+        let invalid_post = json!({
+            "id": "102",
+            "title": "Invalid Post",
+            "content": "Content",
+            "user_id": "999"
+        });
+
+        // Valid FK
+        assert!(posts_table
+            .add_row_with_fk(&db, valid_post, Some(&[("users", "user_id")]))
+            .is_ok());
+
+        // Invalid FK
+        assert!(posts_table
+            .add_row_with_fk(&db, invalid_post, Some(&[("users", "user_id")]))
+            .is_err());
+    }
 }