The present invention relates generally to sweetener compositions comprising non-caloric or low-caloric high-potency sweeteners and methods for making and using them. In particular, the present invention relates to different sweetener compositions comprising at least one non-caloric or low-caloric natural and/or synthetic high-potency sweetener, at least one sweet taste improving composition, and at least one preservative. The present invention also relates to sweetener compositions and methods that can improve the tastes of non-caloric or low-caloric natural and/or synthetic, high-potency sweeteners by imparting a more sugar-like taste or characteristic. In particular, the sweetener compositions and methods provide a more sugar-like temporal profile, including sweetness onset and sweetness linger, and/or a more sugar-like flavor profile.