Blockade of CTLA-4 and PD-1, members of the B7/CD28 family, have proven to be the most successful cancer immunotherapies to date. While the current therapeutic focus remains on B7/CD28 family members, novel immunoregulatory pathways are being uncovered as potential targets for oncology research and cancer immunotherapy. In this presentation, we discuss some of the next generation of novel immune checkpoint molecules, including Butyrophilins (BTNs), leukocyte immunoglobulin-like receptors (LILRs), and V-Set and Immunoglobulin domain containing (VSIGs). Specifically, we will present data demonstrating that bioactive recombinant Butyrophilin proteins (BTN1A1, BTN2A2, and BTN3A1) are T cell inhibitory modulators that inhibit cytokine secretion and cell proliferation on anti-CD3 activated T cells. We will also show data identifying ANGPTL proteins as novel LILR receptors and discuss a novel group of proteins termed V-Set And Immunoglobulin Domain-Containing (VSIG).