The rate integrating gyroscope (RIG) acting as a Foucault pendulum like mechanical integrator, has great potential toward emerging applications above consumer grade such as self driving car, drone, and robot. An ideal RIG intrinsically has distinct advantages over the conventional rate gyroscope (RG), such as direct angle measurement without numerical rate integration noise, stable scale factor, and broad mechanical dynamic range and bandwidth. In this talk, I will discuss the challenges and practical approaches in R&D for the commercialization of MEMS RIG. The contents are mainly based on our recent published works as below. [1] R. Gando, et al .., “A MEMS Rate Integrating Gyroscope Based On Catch and release Mechanism For Low noise Conti nuous Angle Measurement”, in Proc. IEEE 31th Int. Conf. Micro Elect. Mech. Syst., 2018, pp. 944 947. [2] S. Kaji, R. Gando. et al .., “A <100 ppb/K Frequency Matching Temperature Stability MEMS Rate Integrating Gyroscope Enabled by Donut Mass Structure” Structure”, in Proc . MEMS 2020, pp. 263 266. [3] R. Gando et al .., “A Compact Microcontroller based MEMS Rate Integrating Gyroscope Module with Automatic Asymmetry Calibration”, in Proc. IEEE 33th Int. Conf. Micro Elect. Mech. Syst., 2020, pp. 1296 1299 [4] D. Ono R. Gando and Y. Tomizawa, “Demonstration of Trajectory Estimation using A Mobile MEMS Rate Integrating Gyroscope Module,” in Proc 2020 IEEE International Symposium on Inertial Sensors and Systems (INERTIAL), 2020,pp.12,doi:10.1109/INERTIAL48129.2020.9090025.