This document reviews different types of hemopoietic growth factors called colony stimulating factors (CSFs), including their synthesis, effects on cells, and potential clinical applications and side effects. It discusses granulocyte-macrophage CSF (GM-CSF), granulocyte CSF (G-CSF), macrophage CSF (M-CSF), and multi-CSF, and their roles in stimulating various blood cell types. It also reviews early clinical trials using G-CSF and potential future directions using GM-CSF to treat cancers.