Different physical and biological processes prevail at different scales. As a consequence, small-scale experiments or local observations provide limited insights into regional or global phenomena. One solution is to incorporate spatial scale explicitly into the experimental and sampling design of field studies, to provide a broader, landscape view of ecology. Here we examine spatial patterns in corals on the Great Barrier Reef, across a spectrum of scales ranging from metres to more than 1,700 km. Our study is unusual because we explore large-scale patterns of a process (recruitment by juveniles) as well as patterns of adult abundance, revealing the relationship between the two. We show that coral-reef assemblages that are similar in terms of abundance may nonetheless show profound differences in dynamics and turnover, with major implications for their ecology, evolution and management.