Abstract: A mobile intra-operative microscopic diagnosis laboratory capable of analyzing fresh tissue specimens and providing intra-operative consultation within 20 minutes is described. The mobile laboratory is preferably a van and contains a cryostat for freezing the fresh tissue specimens and a means for cutting the specimens. In addition, it also contains the means for reading the slides to make microscopic diagnosis and a means for handling for fresh tissue and a means for indicating various locations in the specimen, preferably by inking them. It preferably contains a stainer for staining the samples and an intercom for communicating the microscopic diagnosis back to the operating room.