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SC make and break junctions among themselves and with different types of germ cells. Major junctions formed by SC are tight junctions, anchoring junctions, ectoplasmic specialization, tubulobulbar complexes, and communication junctions. Tight junctions are present between adjacent SC at the level of the blood–testis barrier and function as a semipermeable barrier – the barrier function. Tight junctions divide SC into basal and adluminal, preventing mixing of molecules in the two compartments – the fence function. Anchoring junctions include adherens junctions (also known as zonula adherens), focal contacts or adhesions, desmosomes, and hemidesmosomes. All these anchoring junctions are biochemically and structurally different from one another and mainly function to connect adjacent cells to one another or to extracellular matrix through cytoskeleton, thus maintaining tissue integrity. Anchoring junctions also function in signal transduction to regulate cell proliferation, differentiation, and translocation. Ectoplasmic specialization is a modified form of adherent junctions and mainly functions in spermiation and maintenance of other junctions present between adjacent SC and, SC and germ cells. Tubulobulbar complexes, also a modified form of zonula adherens, are present between adjacent SC at the level of tight junctions and between SC and mature spermatids ready for spermiation. Focal contacts are actin‐based junctions between testicular cells and extracellular matrix and play an adhesive function at ectoplasmic specialization. Desmosomes are intermediate filament‐based junctions found between SC and SC, and SC and germ cells. Hemidesmosomes are intermediate filament‐based junctions found only between SC and basal lamina; these have adhesive function. Communication junctions are either chemical synapses or gap junctions. Gap junctions, intercellular channels formed by connexons, transduce signals between SC and germ cells and thus participate in germ cell translocation. Gap junctions are present between SC and SC, SC and germ cells, and between two Leydig cells [34].