diff --git a/src/Temporalio/Client/ITemporalClientExtensions.cs b/src/Temporalio/Client/ITemporalClientExtensions.cs
index 2beb2d26..b1c6a91e 100644
--- a/src/Temporalio/Client/ITemporalClientExtensions.cs
+++ b/src/Temporalio/Client/ITemporalClientExtensions.cs
@@ -43,6 +43,49 @@ public static async Task<TResult> ExecuteWorkflowAsync<TWorkflow, TResult>(
             return await handle.GetResultAsync(rpcOptions: options.Rpc).ConfigureAwait(false);
         }
 
+        /// <summary>
+        /// Signal and (optionally) start a workflow via lambda invoking the signalWithStart method.
+        /// </summary>
+        /// <typeparam name="TWorkflow">Workflow class type.</typeparam>
+        /// <param name="client">Client to use.</param>
+        /// <param name="workflowRunCall">Invocation of workflow run method with a result.</param>
+        /// <param name="signalCall">Invocation of signal method without a result.</param>
+        /// <param name="options">Start workflow options. ID and TaskQueue are required.</param>
+        /// <returns>Workflow handle for the started workflow.</returns>
+        /// <exception cref="ArgumentException">Invalid run call or options.</exception>
+        /// <exception cref="Exceptions.RpcException">Server-side error.</exception>
+        public static async Task<WorkflowHandle<TWorkflow>> SignalWorkflowWithStartAsync<TWorkflow>(
+            this ITemporalClient client,
+            Expression<Func<TWorkflow, Task>> workflowRunCall,
+            Expression<Func<TWorkflow, Task>> signalCall,
+            WorkflowOptions options)
+        {
+            options.SignalWithStart(signalCall);
+            return await client.StartWorkflowAsync(workflowRunCall, options).ConfigureAwait(false);
+        }
+
+        /// <summary>
+        /// Signal and (optionally) start a workflow via lambda invoking the signalWithStart method.
+        /// </summary>
+        /// <typeparam name="TWorkflow">Workflow class type.</typeparam>
+        /// <typeparam name="TResult">Workflow result type.</typeparam>
+        /// <param name="client">Client to use.</param>
+        /// <param name="workflowRunCall">Invocation of workflow run method with a result.</param>
+        /// <param name="signalCall">Invocation of signal method without a result.</param>
+        /// <param name="options">Start workflow options. ID and TaskQueue are required.</param>
+        /// <returns>Workflow handle for the started workflow.</returns>
+        /// <exception cref="ArgumentException">Invalid run call or options.</exception>
+        /// <exception cref="Exceptions.RpcException">Server-side error.</exception>
+        public static async Task<WorkflowHandle<TWorkflow, TResult>> SignalWorkflowWithStartAsync<TWorkflow, TResult>(
+            this ITemporalClient client,
+            Expression<Func<TWorkflow, Task<TResult>>> workflowRunCall,
+            Expression<Func<TWorkflow, Task>> signalCall,
+            WorkflowOptions options)
+        {
+            options.SignalWithStart(signalCall);
+            return await client.StartWorkflowAsync(workflowRunCall, options).ConfigureAwait(false);
+        }
+
         /// <summary>
         /// Shortcut for
         /// <see cref="ITemporalClient.StartWorkflowAsync{T}(Expression{Func{T, Task}}, WorkflowOptions)" />
@@ -158,4 +201,4 @@ public static async IAsyncEnumerable<WorkflowHistory> ListWorkflowHistoriesAsync
         }
 #endif
     }
-}
\ No newline at end of file
+}