Fibrin-binding peptides having high binding affinity and excellent physical characteristics compared to previously known fibrin-binding peptides are provided. These fibrin-binding peptides may be conjugated to a detectable label or a therapeutic agent and used to detect and facilitate treatment of pathological conditions associated with the presence of fibrin such as thrombic, angiogenic and neoplastic conditions. These peptides may be used in imaging processes such as MRI, ultrasound and nuclear medicine imaging (e.g. PET, scintigraphic imaging, etc.). The peptides may also be used therapeutically. The present invention also provides processes and methods for making and using such peptides and conjugates thereof.