Heparin-induced thrombocytopenia (HIT) is a serious complication that can arise as a result of heparin-based antithrombotic therapy, characterized by low platelet counts with a paradoxical high risk of thrombosis. If it goes unrecognized, HIT has potentially devastating consequences, including amputation and even death, due to thromboembolic events. Guidelines for HIT emphasize careful screening of platelet counts in at-risk patients, immediate cessation of heparin if a drop in platelet count is detected, and immediate substitution with an alternative antithrombotic therapy. Adherence to these guidelines requires an astute awareness of HIT, its clinical presentation and diagnosis, and its proper management among hospital-based caregivers.