diff --git a/latan/Global.cpp b/latan/Global.cpp
index 61475df..5830846 100644
--- a/latan/Global.cpp
+++ b/latan/Global.cpp
@@ -26,3 +26,21 @@ using namespace Latan;
 const string Env::fullName = PACKAGE_STRING;
 const string Env::name     = PACKAGE_NAME;
 const string Env::version  = PACKAGE_VERSION;
+
+template <>
+float Latan::strTo<float>(const string &str)
+{
+    return strtof(str.c_str(), (char **)NULL);
+}
+
+template <>
+double Latan::strTo<double>(const string &str)
+{
+    return strtod(str.c_str(), (char **)NULL);
+}
+
+template <>
+int Latan::strTo<int>(const string &str)
+{
+    return (int)(strtol(str.c_str(), (char **)NULL, 10));
+}
diff --git a/latan/Global.hpp b/latan/Global.hpp
index 6f17898..44d1b13 100644
--- a/latan/Global.hpp
+++ b/latan/Global.hpp
@@ -49,7 +49,7 @@ namespace Env
 
 // string conversions
 template <typename T>
-T strTo(std::string str)
+T strTo(const std::string &str)
 {
     T buf;
     std::istringstream stream(str);
@@ -59,8 +59,16 @@ T strTo(std::string str)
     return buf;
 }
 
+//// optimized specializations
+template <>
+float strTo<float>(const std::string &str);
+template <>
+double strTo<double>(const std::string &str);
+template <>
+int strTo<int>(const std::string &str);
+
 template <typename T>
-std::string strFrom(T x)
+std::string strFrom(const T x)
 {
     std::ostringstream stream;