Viscoelastic testing (VET) has evolved significantly since its inception in the mid-20th century, when it was first developed to guide transfusion strategies in trauma and surgical patients. Initially, VET technologies such as TEG and ROTEM assessed clot formation by measuring the mechanical resistance of a pin or piston within a blood sample. Recent advances have introduced automated, cartridge-based systems and novel detection methods—including resonance frequency and ultrasound-based sonorheometry—these new systems allow for more precise, rapid, and user-friendly assessment of clot dynamics at the point of care. VET is now indicated for a wide range of clinical scenarios where complex coagulopathy is anticipated, including trauma, cardiac surgery, liver transplantation, obstetric hemorrhage, and hematologic disorders such as DIC. Its use is expanding into new populations, including pediatric cardiac surgery, patients with inflammatory bowel disease, and those with COVID-19. However, VET remains limited in its ability to reliably detect therapeutic anticoagulants and certain congenital bleeding disorders, such as von Willebrand disease and deficiencies of protein C, S, and antithrombin. Technical limitations, including potential discrepancies between in vitro and in vivo clot formation, and lack of FDA approval for pediatric use have imposed implementation barriers to centers interested in pediatric VET. Looking forward, the integration of VET data with electronic medical records, the development of predictive models, artificial intelligence, and continued innovation in platelet function assessment and detection technologies are poised to enhance the clinical utility of VET. As guidelines and evidence continue to evolve, VET is positioned to become an increasingly important tool for real-time, individualized management of coagulopathy in diverse patient populations.