In the evolutionary biology of the Modern Synthesis the study of patterns refers to how to identify and systematise order in lineages, looking for hierarchies or for branching/splitting events in the tree of life, whereas the resulting order is supposed to be due to underlying processes or mechanisms. But patterns and processes play distinct roles in evo-devo: four different views on the role of patterns and processes in descriptions and explanations of development and evolution: A) transformational; B) generative; C) processual; (...) and D) complex are reviewed in this paper. Then, this discussion is related to two issues in evo-devo: homology and variation. (shrink)