Over the years, many different tyrosine and serine/threonine protein kinases have been selected as candidates for drug discovery activities in oncology research, based either on their overexpression and/or dysfunction in a particular organ or tissue, or through their association in deregulated signal transduction/cell cycle pathways. This review summarises current preclinical and clinical knowledge of ATP-competitive, small molecule kinase inhibitors, and receptor or ligand-competitive antibodies of selected protein kinases in which drug discovery and development activities have advanced with some success.