Solid solution strengthened Co-base superalloys have recently rekindled interest due to their excellent microstructural stability and mechanical strength at high temperatures. Therefore, understanding the deformation behaviour of these alloys over a wide range of temperature, strain rate, and stress is imperative. Earlier studies have shown that inherent low stacking fault energy (SFE) lead to a distinct high-temperature deformation and creep behaviour at elevated temperatures (>0.3 Tm) in solid solution strengthened cobalt-base superalloys compared to the wrought Ni-base superalloys. Moreover, the microstructural characterization studies revealed the presence of temperature-dependent substructural features such as dislocation dipoles, stacking faults, and solute segregation near the partials (i.e., Suzuki segregation). However, the fundamental mechanism for the formation of these substructural features and their contribution towards deformation mechanisms is not elucidated. Thus, the present study aims to understand the substructure evolution in a solid solution strengthened Co-base superalloy Co-22Cr-22Ni-14W-2Fe-1.25Mn-0.1C over a wide range of temperature (RT – 0.9Tm ) and strain rate. As a part of this work, extensive mechanical testing was conducted at various strain rates (10-4 – 10-1 s-1), stress levels (30 – 500 MPa), and temperatures (RT – 1200 °C). Further, detailed microstructural characterization studies were performed on the post-deformed and interrupted specimens using transmission electron microscopy (TEM) and electron backscattered diffraction (EBSD). By correlating these findings with the deformation behaviour, the plausible region-wise deformation mechanisms are proposed and will be discussed in the seminar.