diff --git a/viper.go b/viper.go
index fce13b1..3991ad8 100644
--- a/viper.go
+++ b/viper.go
@@ -732,13 +732,16 @@ func (v *Viper) Unmarshal(rawVal interface{}) error {
 }
 
 // defaultDecoderConfig returns default mapsstructure.DecoderConfig with suppot
-// of time.Duration values
+// of time.Duration values & string slices
 func defaultDecoderConfig(output interface{}) *mapstructure.DecoderConfig {
 	return &mapstructure.DecoderConfig{
 		Metadata:         nil,
 		Result:           output,
 		WeaklyTypedInput: true,
-		DecodeHook:       mapstructure.StringToTimeDurationHookFunc(),
+		DecodeHook:       mapstructure.ComposeDecodeHookFunc(
+			mapstructure.StringToTimeDurationHookFunc(),
+			mapstructure.StringToSliceHookFunc(","),
+		),
 	}
 }