This review summarizes those methodsestablished and emerging- of semen assessment whose outcome intents revealing its potential fertility and, as a carry-over concept, that of the sire whose semen we examined. The review does not, however, focus on the wide display of current techniques designed to explore specific or multiple sets of sperm attributes essential for fertilization but on two basic concerns present: the heterogeneity of the sperm suspension and the multitude of attributes required for each spermatozoon to be fertile; concepts that shadow our diagnostic capabilities. The review points out advancements in the exploration of the genome, the transcriptome, and the proteome of both spermatozoa and the seminal plasma which unveil how spermatozoa modulate their own survival and signal to the environment when displaying degenerative changes. Specific seminal plasma components, both among individuals and portions of the ejaculate, not only relate to survival but also signal differential immune tolerance by the female with a previously unattended linkage to fertility. Lastly it foresees how Cytomics, combining novel designed motility analyzers, flow cytometers and enhanced digital imaging shall dominate the landscape of andrological laboratories and enable quick determinations on huge sperm numbers for markers highly relevant to sperm function and hence, for fertility.