In this paper we report on the patterning challenges for the integration of Spin-Transfer Torque Magneto-Resistive- Random-Access Memory (STT MRAM). An overview of the different patterning approaches that have been evaluated in the past decade is presented. Plasma based etching, wet echting, but also none subtractive pattering approaches are covered. The paper also reports on the patterning strategies, currently under investigation at imec.