diff --git a/libc/Makefile b/libc/Makefile
index ecbfe8a5..6cb9e3af 100644
--- a/libc/Makefile
+++ b/libc/Makefile
@@ -116,7 +116,9 @@ string/strcoll.o \
 string/strcpy.o \
 string/strcspn.o \
 string/strdup.o \
+string/strerror_l.o \
 string/strerror.o \
+string/strerror_r.o \
 string/strlcpy.o \
 string/strlen.o \
 string/strncasecmp.o \
diff --git a/libc/include/string.h b/libc/include/string.h
index fbad9f5b..4cb13225 100644
--- a/libc/include/string.h
+++ b/libc/include/string.h
@@ -50,6 +50,7 @@ int strcoll_l(const char*, const char*, locale_t);
 size_t strcspn(const char*, const char*);
 char* strcpy(char* __restrict, const char* __restrict);
 char* strdup(const char*);
+int strerror_r(int, char*, size_t);
 size_t strlcpy(char* __restrict, const char* __restrict, size_t);
 size_t strlen(const char*);
 char* strncat(char* __restrict, const char* __restrict, size_t);
@@ -67,25 +68,22 @@ int strverscmp(const char*, const char*);
 size_t strxfrm(char* __restrict, const char* __restrict, size_t);
 size_t strxfrm_l(char* __restrict, const char* __restrict, size_t, locale_t);
 
-/* TODO: These are not implemented in sortix libc yet. */
-#if defined(__SORTIX_SHOW_UNIMPLEMENTED)
-char* strerror_l(int, locale_t);
-int strerror_r(int, char*, size_t);
-#endif
-
 #if defined(_SORTIX_SOURCE) || defined(_GNU_SOURCE)
 char* strchrnul(const char* str, int c);
 #endif
 
 #if defined(_SORTIX_SOURCE)
 const char* sortix_strerror(int errnum);
+const char* sortix_strerror_l(int, locale_t);
 const char* sortix_strsignal(int signum);
 #endif
 #if defined(_SOURCE_SOURCE) && __SORTIX_STDLIB_REDIRECTS
 const char* strerror(int errnum) asm ("sortix_strerror");
+const char* strerror_l(int, locale_t) asm ("sortix_strerror_l");
 const char* strsignal(int signum) asm ("sortix_strsignal");
 #else
 char* strerror(int errnum);
+char* strerror_l(int, locale_t);
 char* strsignal(int signum);
 #endif
 
diff --git a/libc/string/strerror_l.cpp b/libc/string/strerror_l.cpp
new file mode 100644
index 00000000..d91528da
--- /dev/null
+++ b/libc/string/strerror_l.cpp
@@ -0,0 +1,36 @@
+/*******************************************************************************
+
+    Copyright(C) Jonas 'Sortie' Termansen 2013.
+
+    This file is part of the Sortix C Library.
+
+    The Sortix 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 3 of the License, or (at your
+    option) any later version.
+
+    The Sortix 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 Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
+
+    string/strerror_l.cpp
+    Convert error code to a string.
+
+*******************************************************************************/
+
+#define __SORTIX_STDLIB_REDIRECTS 0
+#include <string.h>
+
+extern "C" const char* sortix_strerror_l(int errnum, locale_t /*locale*/)
+{
+	return sortix_strerror(errnum);
+}
+
+extern "C" char* strerror_l(int errnum, locale_t locale)
+{
+	return (char*) sortix_strerror_l(errnum, locale);
+}
diff --git a/libc/string/strerror_r.cpp b/libc/string/strerror_r.cpp
new file mode 100644
index 00000000..08b992ca
--- /dev/null
+++ b/libc/string/strerror_r.cpp
@@ -0,0 +1,36 @@
+/*******************************************************************************
+
+    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012, 2013.
+
+    This file is part of the Sortix C Library.
+
+    The Sortix 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 3 of the License, or (at your
+    option) any later version.
+
+    The Sortix 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 Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
+
+    string/strerror_r.cpp
+    Convert error code to a string.
+
+*******************************************************************************/
+
+#include <errno.h>
+#include <string.h>
+
+extern "C" int strerror_r(int errnum, char* dest, size_t dest_len)
+{
+	const char* msg = sortix_strerror(errnum);
+	if ( !msg )
+		return -1;
+	if ( strlcpy(dest, msg, dest_len) != strlen(msg) )
+		errno = ERANGE;
+	return 0;
+}