This thesis explores the interactions between the architect Christopher Alexander and the visionary grouping of architects known as Team 10, with a focus on Alexander's participation in one of Team 10's famous meetingsa t the Abbaye de Royaumont in 1962. Both Alexander and Team 10 went on to make important contributions to architectural history and theory. Both were motivated by a critical appraisal of the high modernism of CIAM (Congrès Internationaux d’Architecture Moderne) to search for new solutions. This paper uncovers some striking parallels in their thinking and approaches, both explicit and implicit. Yet after 1962 their thinking took them in different and increasingly opposing directions. Questions explored include why these differences came about, to what extent they were fundamental, and what a continued collaboration might have achieved.