The cells comprising all solid tissues in our bodies are held together by a family of adhesion molecules known as cadherins. A network of intracellular fibers known as actin strengthens the adhesive contact, but the molecular mechanisms connecting actin filaments to cadherins are poorly understood. Tang and Brieher found that a protein known as α-actinin 4 is crucial for assembling actin at cadherin-mediated adhesive junctions. Mutations in α-actinin 4 can lead to a type of inherited kidney disease. Tang and Brieher demonstrated that a mutant form of α-actinin 4 that causes disease is not able to assemble actin at cadherin adhesive junctions. This new work extends our knowledge as to how these adhesive junctions form and function and is yet another example of how basic research in cell biology can provide insight into human disease.