Unconventional superconductivity refers to those superconductivity phenomena that cannot be adequately explained by the traditional BCS theory. A significant focus within this field is on cuprates, due to rich applications and other unconventional phases. It is widely accepted that strong electronic correlations play a dominant role in cuprates, yet this alone does not fully explain the robust high-Tc superconductivity. In this talk, I discuss the recent theoretical and experimental progress on the cooperation of strong correlation and electron-phonon coupling. A key finding from comparing experiments with theory reveals a significant spectral feature that was not anticipated by the Hubbard model. This feature has been quantitatively accounted for through polaronic effects, as demonstrated using using our hybrid numerical method. The synergy between these two interactions appears to favor d-wave pairing instability. Building on these insights, I will discuss potential cooperative mechanisms in nickelate superconductors and magic-angle twisted bilayer graphene.