diff --git a/configure.ac b/configure.ac
index 711ad618..1c3ad2da 100755
--- a/configure.ac
+++ b/configure.ac
@@ -108,6 +108,7 @@ case "${with_crypto_library}" in
     AC_DEFINE([USE_CRYPTO_MBEDTLS], [1], [Use mbed TLS library])
     ;;
 esac
+ss_SODIUM
 
 dnl Checks for Apple CommonCrypto API
 AC_ARG_ENABLE(applecc,
@@ -299,16 +300,12 @@ AC_CHECK_LIB(socket, connect)
 dnl Checks for library functions.
 AC_CHECK_FUNCS([malloc memset socket])
 
-AC_CHECK_LIB([sodium], [sodium_init], ,
-     [ AC_MSG_ERROR([Couldn't find libsodium. Try installing libsodium-dev@<:@el@:>@.])])
-
 dnl Add define for libudns to enable IPv6 support
 dnl This is an option defined in the origin configure script
 AC_DEFINE([HAVE_IPv6], [1], [Enable IPv6 support in libudns])
 
-AC_CHECK_LIB([udns], [dns_dnlen], ,[AC_MSG_ERROR([Couldn't find libudns. Try installing libudns-dev or udns-devel.])])
-
-AC_CHECK_LIB([ev], [ev_loop_destroy], ,[AC_MSG_ERROR([Couldn't find libev. Try installing libev-dev@<:@el@:>@.])])
+AC_CHECK_LIB([udns], [dns_dnlen], [LIBS="-ludns $LIBS"], [AC_MSG_ERROR([Couldn't find libudns. Try installing libudns-dev or udns-devel.])])
+AC_CHECK_LIB([ev], [ev_loop_destroy], [LIBS="-lev $LIBS"], [AC_MSG_ERROR([Couldn't find libev. Try installing libev-dev@<:@el@:>@.])])
 
 AM_COND_IF([ENABLE_DOCUMENTATION],
   [AC_CONFIG_FILES([doc/Makefile])
diff --git a/m4/sodium.m4 b/m4/sodium.m4
new file mode 100644
index 00000000..dd03503c
--- /dev/null
+++ b/m4/sodium.m4
@@ -0,0 +1,30 @@
+dnl Check to find the libsodium headers/libraries
+
+AC_DEFUN([ss_SODIUM],
+[
+
+    AC_ARG_WITH(sodium,
+    AS_HELP_STRING([--with-sodium=DIR], [The Sodium crypto library base directory, or:]),
+    [sodium="$withval"
+     CFLAGS="$CFLAGS -I$withval/include"
+     LDFLAGS="$LDFLAGS -L$withval/lib"]
+    )
+
+    AC_ARG_WITH(sodium-include,
+    AS_HELP_STRING([--with-sodium-include=DIR], [The Sodium crypto library headers directory (without trailing /sodium)]),
+    [sodium_include="$withval"
+     CFLAGS="$CFLAGS -I$withval"]
+    )
+
+    AC_ARG_WITH(sodium-lib,
+    AS_HELP_STRING([--with-sodium-lib=DIR], [The Sodium crypto library library directory]),
+    [sodium_lib="$withval"
+     LDFLAGS="$LDFLAGS -L$withval"]
+    )
+
+    AC_CHECK_LIB(sodium, sodium_init,
+    [LIBS="-lsodium $LIBS"],
+    [AC_MSG_ERROR([The Sodium crypto library libraries not found.])]
+    )
+
+])