diff --git a/conform/data/threads.h-data b/conform/data/threads.h-data
index 70b2fe0..d7c562e 100644
--- a/conform/data/threads.h-data
+++ b/conform/data/threads.h-data
@@ -16,6 +16,7 @@ type thrd_t
 type thrd_start_t
 type mtx_t
 type once_flag
+type cnd_t
 
 function int thrd_create (thrd_t*, thrd_start_t, void*)
 function int thrd_equal (thrd_t, thrd_t)
@@ -35,6 +36,13 @@ function void mtx_destroy (mtx_t*)
 
 function void call_once (once_flag*, void (*)(void))
 
+function int cnd_init (cnd_t*)
+function int cnd_signal (cnd_t*)
+function int cnd_broadcast (cnd_t*)
+function int cnd_wait (cnd_t*, mtx_t*)
+function int cnd_timedwait (cnd_t*, mtx_t*, const struct timespec*)
+function void cnd_destroy (cnd_t*)
+
 #include "time.h-data"
 
 #endif
diff --git a/nptl/Makefile b/nptl/Makefile
index 7d2b83f..ddef534 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -142,7 +142,8 @@ libpthread-routines = nptl-init vars events version pt-interp \
 		      thrd_create thrd_current thrd_detach thrd_equal \
 		      thrd_exit thrd_join thrd_sleep thrd_yield \
 		      mtx_destroy mtx_init mtx_lock mtx_timedlock \
-		      mtx_trylock mtx_unlock call_once
+		      mtx_trylock mtx_unlock call_once cnd_broadcast \
+		      cnd_destroy cnd_init cnd_signal cnd_timedwait cnd_wait
 #		      pthread_setuid pthread_seteuid pthread_setreuid \
 #		      pthread_setresuid \
 #		      pthread_setgid pthread_setegid pthread_setregid \
diff --git a/nptl/Versions b/nptl/Versions
index b055860..53e6b9a 100644
--- a/nptl/Versions
+++ b/nptl/Versions
@@ -269,7 +269,8 @@ libpthread {
   GLIBC_2.27 {
     thrd_create; thrd_current; thrd_detach; thrd_equal; thrd_exit; thrd_join;
     thrd_sleep; thrd_yield; mtx_init; mtx_lock; mtx_timedlock; mtx_trylock;
-    mtx_unlock; mtx_destroy; call_once;
+    mtx_unlock; mtx_destroy; call_once; cnd_broadcast; cnd_destroy; cnd_init;
+    cnd_signal; cnd_timedwait; cnd_wait; mtx_destroy;
   }
 
   GLIBC_PRIVATE {
diff --git a/nptl/cnd_broadcast.c b/nptl/cnd_broadcast.c
new file mode 100644
index 0000000..8e5f165
--- /dev/null
+++ b/nptl/cnd_broadcast.c
@@ -0,0 +1,28 @@
+/* C11 thread conditional broadcast implementation.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "thrd_priv.h"
+
+/* Unblock all threads currently waiting on condition variable pointed
+   by cond.  */
+int
+cnd_broadcast (cnd_t *cond)
+{
+  int err_code = __pthread_cond_broadcast ((pthread_cond_t*) cond);
+  return thrd_err_map (err_code);
+}
diff --git a/nptl/cnd_destroy.c b/nptl/cnd_destroy.c
new file mode 100644
index 0000000..4b46132
--- /dev/null
+++ b/nptl/cnd_destroy.c
@@ -0,0 +1,28 @@
+/* C11 threads conditional destroy implementation.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "thrd_priv.h"
+#include "pthreadP.h"
+
+/* Destroy condition variable pointed by cond and free all of its
+   resources.  */
+void
+cnd_destroy (cnd_t *cond)
+{
+  __pthread_cond_destroy ((pthread_cond_t *) cond);
+}
diff --git a/nptl/cnd_init.c b/nptl/cnd_init.c
new file mode 100644
index 0000000..eb8a544
--- /dev/null
+++ b/nptl/cnd_init.c
@@ -0,0 +1,33 @@
+/* C11 thread conditional initialization implementation.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <stdalign.h>
+
+#include "thrd_priv.h"
+
+/* Initialize new condition variable pointed by cond.  */
+int
+cnd_init (cnd_t *cond)
+{
+  _Static_assert (sizeof (cnd_t) == sizeof (pthread_cond_t), "cnd_t size");
+  _Static_assert (alignof (cnd_t) == alignof (pthread_cond_t),
+		  "cnd_t alignment");
+
+  int err_code = __pthread_cond_init ((pthread_cond_t *)cond, NULL);
+  return thrd_err_map (err_code);
+}
diff --git a/nptl/cnd_signal.c b/nptl/cnd_signal.c
new file mode 100644
index 0000000..e843957
--- /dev/null
+++ b/nptl/cnd_signal.c
@@ -0,0 +1,28 @@
+/* C11 threads conditional signal implementation.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "thrd_priv.h"
+
+/* Unblock one thread that currently waits on condition variable pointed
+   by cond.  */
+int
+cnd_signal (cnd_t *cond)
+{
+  int err_code = __pthread_cond_signal ((pthread_cond_t *) cond);
+  return thrd_err_map (err_code);
+}
diff --git a/nptl/cnd_timedwait.c b/nptl/cnd_timedwait.c
new file mode 100644
index 0000000..b3c60e8
--- /dev/null
+++ b/nptl/cnd_timedwait.c
@@ -0,0 +1,31 @@
+/* C11 threads conditional timed wait implementation.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "thrd_priv.h"
+
+/* Block current thread on the condition variable until condition variable
+   pointed by cond is signaled or time pointed by time_point is reached.  */
+int
+cnd_timedwait (cnd_t *restrict cond, mtx_t *restrict mutex,
+		const struct timespec* restrict time_point)
+{
+  int err_code = __pthread_cond_timedwait ((pthread_cond_t *) cond,
+					   (pthread_mutex_t *) mutex,
+					   time_point);
+  return thrd_err_map (err_code);
+}
diff --git a/nptl/cnd_wait.c b/nptl/cnd_wait.c
new file mode 100644
index 0000000..298d049
--- /dev/null
+++ b/nptl/cnd_wait.c
@@ -0,0 +1,28 @@
+/* C11 threads conditional wait implementaiton.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "thrd_priv.h"
+
+/* Block current thread on the condition variable pointed by cond.  */
+int
+cnd_wait (cnd_t *cond, mtx_t *mutex)
+{
+  int err_code = __pthread_cond_wait ((pthread_cond_t *) cond,
+				      (pthread_mutex_t *) mutex);
+  return thrd_err_map (err_code);
+}
diff --git a/sysdeps/nptl/threads.h b/sysdeps/nptl/threads.h
index 53fe731..568e2d4 100644
--- a/sysdeps/nptl/threads.h
+++ b/sysdeps/nptl/threads.h
@@ -57,6 +57,12 @@ typedef union
   long int __align __LOCK_ALIGNMENT;
 } mtx_t;
 
+typedef union
+{
+  char __size[__SIZEOF_PTHREAD_COND_T];
+  __extension__ long long int __align __LOCK_ALIGNMENT;
+} cnd_t;
+
 /* Threads functions.  */
 
 /* Create a new thread executing the function __func.  Arguments to __func
@@ -136,6 +142,34 @@ extern void mtx_destroy (mtx_t *__mutex);
    All calls must be made with the same __flag object.  */
 extern void call_once (once_flag *__flag, void (*__func)(void));
 
+
+/* Condition variable functions.  */
+
+/* Initialize new condition variable pointed by __cond.  */
+extern int cnd_init (cnd_t *__cond);
+
+/* Unblock one thread that currently waits on condition variable pointed
+   by __cond.  */
+extern int cnd_signal (cnd_t *__cond);
+
+/* Unblock all threads currently waiting on condition variable pointed by
+   __cond.  */
+extern int cnd_broadcast (cnd_t *__cond);
+
+/* Block current thread on the condition variable pointed by __cond.  */
+extern int cnd_wait (cnd_t *__cond, mtx_t *__mutex);
+
+/* Block current thread on the condition variable until condition variable
+   pointed by __cond is signaled or time pointed by __time_point is
+   reached.  */
+extern int cnd_timedwait (cnd_t *__restrict __cond,
+			  mtx_t *__restrict __mutex,
+			  const struct timespec *__restrict __time_point);
+
+/* Destroy condition variable pointed by __cond and free all of its
+   resources.  */
+extern void cnd_destroy (cnd_t *__cond);
+
 __END_DECLS
 
 #endif /* _THREADS_H */
