The surge of enthusiastic interest in inter-organisational collaboration, especially in technology-intensive sectors, over the last decade has tended to mask the longer-term trends towards increased co-operation. The paper uses recent empirical research by the authors to discuss these trends and to examine some of the significant problems involved in the management of collaborations. We conclude that collaboration is an evolutionary process in which management skills of learning, mutual adaptation and accommodation can be more important to the eventual success of a collaboration than rigid adherence to an ab initio schedule of targets and objectives. Collaborative product development may be more costly, slower, less efficient and more difficult to manage than independent product development but our research also suggests that, where successfully managed, the benefits can substantially outweigh these problems.