Tumor engineering applies some of the tissue engineering principles in an effort to mimic the in vivo tumor environment by the integrated use of biomaterials that provide the artificial extracellular matrix to cells and biomimetic bioreactors that provide efficient mass transport and adequate physical signals. This approach aims to achieve reliable 3D tumor models that could be used in antitumor drug testing as well as development of personalized medical therapies. In this session, recent advances in development of 3D models of different malignant tumors will be covered and discussed.