diff --git a/README.md b/README.md
index 29bf53c..2e51b7e 100644
--- a/README.md
+++ b/README.md
@@ -50,3 +50,4 @@ For a deeper look into the documentation check in the [thpool.h](https://github.
 | ***thpool_destroy(thpool)***    | This will destroy the threadpool. If jobs are currently being executed, then it will wait for them to finish. |
 | ***thpool_pause(thpool)***      | All threads in the threadpool will pause no matter if they are idle or executing work. |
 | ***thpool_resume(thpool)***      | If the threadpool is paused, then all threads will resume from where they were.   |
+| ***thpool_num_threads_working(thpool)***  | Will return the number of currently working threads.   |
diff --git a/tests/api.sh b/tests/api.sh
new file mode 100755
index 0000000..17f23e3
--- /dev/null
+++ b/tests/api.sh
@@ -0,0 +1,33 @@
+#! /bin/bash
+
+#
+# This file has several tests to check that the API
+# works to an acceptable standard.
+#
+
+. funcs.sh
+
+
+# ---------------------------- Tests -----------------------------------
+
+
+function test_api {
+	echo "Testing API calls.."
+	compile src/api.c
+	output=`./test`
+	if [[ $? != 0 ]]; then
+		 err "$output" "$output"
+		 exit 1
+	fi
+}
+
+
+
+# Run tests
+test_api
+
+
+
+
+
+echo "No API errors"
diff --git a/tests/normal_compile.sh b/tests/normal_compile.sh
index 3613606..aada642 100755
--- a/tests/normal_compile.sh
+++ b/tests/normal_compile.sh
@@ -9,6 +9,7 @@
 # ---------------------------- Tests -----------------------------------
 
 . threadpool.sh
+. api.sh
 . pause_resume.sh
 . heap_stack_garbage.sh
 . memleaks.sh
diff --git a/tests/src/api.c b/tests/src/api.c
new file mode 100644
index 0000000..ad2c1ed
--- /dev/null
+++ b/tests/src/api.c
@@ -0,0 +1,48 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <time.h>
+#include <stdlib.h>
+#include "../../thpool.h"
+
+
+void sleep_2_secs(){
+	sleep(2);
+	puts("SLEPT");
+}
+
+
+int main(int argc, char *argv[]){
+
+	int num = 0;
+	threadpool thpool;
+
+	/* Test if we can get the current number of working threads */
+	thpool = thpool_init(10);
+	thpool_add_work(thpool, (void*)sleep_2_secs, NULL);
+	thpool_add_work(thpool, (void*)sleep_2_secs, NULL);
+	thpool_add_work(thpool, (void*)sleep_2_secs, NULL);
+	thpool_add_work(thpool, (void*)sleep_2_secs, NULL);
+	sleep(1);
+	num = thpool_num_threads_working(thpool);
+	if (thpool_num_threads_working(thpool) != 4) {
+		printf("Expected 4 threads working, got %d", num);
+		return -1;
+	};
+
+	/* Test (same as above) */
+	thpool = thpool_init(5);
+	thpool_add_work(thpool, (void*)sleep_2_secs, NULL);
+	thpool_add_work(thpool, (void*)sleep_2_secs, NULL);
+	sleep(1);
+	num = thpool_num_threads_working(thpool);
+	if (num != 2) {
+		printf("Expected 2 threads working, got %d", num);
+		return -1;
+	};
+
+	// thpool_destroy(thpool);
+
+	// sleep(1); // Sometimes main exits before thpool_destroy finished 100%
+
+	return 0;
+}
diff --git a/thpool.c b/thpool.c
index 4a7fea0..f269899 100644
--- a/thpool.c
+++ b/thpool.c
@@ -253,6 +253,11 @@ void thpool_resume(thpool_* thpool_p) {
 }
 
 
+int thpool_num_threads_working(thpool_* thpool_p){
+	return thpool_p->num_threads_working;
+}
+
+
 
 
 
diff --git a/thpool.h b/thpool.h
index 03edeef..e5d0d1b 100644
--- a/thpool.h
+++ b/thpool.h
@@ -158,6 +158,28 @@ void thpool_resume(threadpool);
  */
 void thpool_destroy(threadpool);
 
+
+/**
+ * @brief Show currently working threads
+ *
+ * Working threads are the threads that are performing work (not idle).
+ *
+ * @example
+ * int main() {
+ *    threadpool thpool1 = thpool_init(2);
+ *    threadpool thpool2 = thpool_init(2);
+ *    ..
+ *    printf("Working threads: %d\n", thpool_num_threads_working(thpool1));
+ *    ..
+ *    return 0;
+ * }
+ *
+ * @param threadpool     the threadpool of interest
+ * @return integer       number of threads working
+ */
+int thpool_num_threads_working(threadpool);
+
+
 #ifdef __cplusplus
 }
 #endif