A low temperature curable coating powder comprising an epoxy functional resin is cured with styrene maleimide in combination with at least one other curing agent such as dicyandiamide, imidazole, or an imidazole adduct. The combination of three curing agents such styrene maleimide, dicyandiamide, and an imidazole or imidazole adduct is useful for achieving gloss control. The coating powder may be curable at temperatures of 300° F. or lower. The coating of heat-sensitive and non-conductive substrates is facilitated with use of such coating powder, although other substrates, such as metal may be coated in accordance with the invention.