The magic of iPS cells is that they can be expanded into large numbers and differentiated into all cell types, so that an initially small number of iPS cells can be used to produce a massive number of cells. However, some cells have proven easier to make than others, which has significant implications on the cost of translating iPS cell research to clinical therapies. A new study by the Koji Eto lab reports that the choice of laminin, a ubiquitous molecule in the human body and commonly used in iPS cell therapies, influences the hematopoietic differentiation of the iPS cells.