Understanding and investigating tumors is carried out by researchers using a number of different methods. One exciting and promising area is 3D tumor models including spheriod and organoid models. They act in similar ways to tumors which means we can use them to gather important information. This ranges from the way tumors react through to how different treatments may work on tumors. Ultimately they may help guide us towards the types of drugs and therapies that could be used to treat tumors. This work gives an overview of these technologies, the types of 3D models available and how they can be used to improve treatments and their applications in personalized medicine.