In this issue, JCS is pleased to present a collection of articles that focus on invadopodia and podosomes. These actin-rich cellular structures (which are also known collectively as invadosomes) establish close contact with the extracellular matrix (ECM) and can degrade ECM components. Invadopodia (which have been visualised in cancer cells) are thought to have a role in metastatic invasion, whereas podosomes (which are found in osteoclasts and other monocytic cells) contribute to bone degradation, among other processes. This issue's Minifocus highlights several important areas of invadosome biology. A schematic overview of invadosome structure and function is presented by Stefan Linder (p. 3009). Next, Philippe Chavrier and colleagues (p. 3015) highlight the role of invadopodia in cancer progression by describing how matrix metalloproteases traffic to, and are secreted at, these sites. On page 3025, Chris Carman explores the evidence that leukocytes employ invadosome-like structures when crossing the endothelial barrier. Finally, Corinne Albiges-Rizo and colleagues (p. 3037) evaluate recent insights into invadosomal actin dynamics and discuss how invadosomes respond to mechanical force. Together, these articles showcase key recent findings on the structure and function of invadosomes, and highlight the diversity of biological settings in which they are important.