Success is

a personal satisfaction and pride in the effort put forth as well as the result. I measure success by the happiness that follows. If I know that I gave my best, and that my best was enough, I feel I've been successful. Of course, there is always joy in positive feedback, but I don't think approval is necessarily a concrete standard of measurement for how successful or unsuccessful one is. If you're able to confidently say, "I'm happy with my work," and more importantly, "I enjoyed doing it," then that's really what matters. Success and happiness go together well, and in my world I can't have one without the other.