Between November 2015 and October 2018, the Wellcome Trust supported a project to develop the [http://www.guidetoimmunopharmacology.org IUPHAR Guide to IMMUNOPHARMACOLOGY] (GtoImmuPdb), based on the GtoPdb schema. The GtoImmuPdb is an open-access resource that brings an immunological perspective to the high-quality, expert-curated pharmacological data found in the existing IUPHAR/BPS Guide to PHARMACOLOGY. Protein targets and ligands relevant to immunopharmacology have been tagged and curated into GtoImmuPdb. These have also been associated with new immunological data types such as immunological processes, cell types, and disease. GtoImmuPdb provides a knowledge base that connects immunology with pharmacology, bringing added value and supporting research and development of drugs targeted at modulating immune, inflammatory or infectious components of the disease.