Climate change results from human and natural modulation of atmospheric constituents, land use changes, and other changes to Earth system components. Some “forcing” agents are responses or feedbacks to observed change underway, like Greenland or Antarctic Ice Sheet or glacial melt as the Earth warms, amongst other “forced” changes. These anthropogenic or natural climate drivers are termed “climate forcing” agents. Spatial and temporal evolution of these forcings are needed as model input to simulate historical climate change and make future projections. Climate forcing science has been evolving parallel to model capability and complexity, with marked growth in the types of forcing agents needed to drive models along with a better understanding of their uncertainties. This talk will provide an overview of “climate forcing” science and elucidate how forcing datasets have evolved over past CMIP phases, highlighting areas of significant progress and remaining uncertainties, in addition to the latest developments expected for CMIP7 in 2025.