Reflecting on 30 years of working with many partners, the author offers some advice to those planning, especially for a first time, to research or write with others. In this article, he discusses when to collaborate, under what terms, and when to cease doing so. It assumes that working with others is, in principle, desirable but says little explicitly on why. Possible reasons could include the idea that if two or more people are involved in a research project, they will normally be able to see more, make fewer mistakes and sustain a higher level of enthusiasm than can one. The author believes that taken as a whole, the collaborative research and writing in which he has been involved has been more rigorous, original and significant than has the solo: it has usually also been more fun for him. (Contains 1 footnote.)