Researchers at Yashraj Biotechnology Ltd. reviewed the diverse biological roles and diagnostic potential of human Galectin-3, a multifunctional β-galactoside-binding lectin. The review covers its involvement in cell adhesion, proliferation, mRNA splicing and apoptosis, and highlights its value as a biomarker in heart failure and in cancers of the thyroid, colon, breast, pancreas, prostate, kidney, brain, and head and neck. It also discusses its potential as a therapeutic target and as an affinity ligand for protein purification.