In this month's CP Stem Cell Biology, we have a brand new protocol describing a method for the sectioning and immunohistochemistry of 3-D organoids (a miniature organ produced in vitro). You can check out the full paper here. In brief, this is a protocol for using iPSC-derived 3-D organoids to assess developmental processes that occur during the formation of the organoid. This protocol is essential for interrogation of disease pathophysiology and development of patient-specific cell replacement therapies using 3-D differentiation protocols.