 BPH is a common disorder of the prostate causing significant lower urinary tract symptoms and negatively affects the quality of life in a substantial proportion of men in North America. According to the National Institutes of Health NIH, BPH affects more than 50 of men over age 60 and as many as 90 of men over the age of 70. Although there are numerous genetic and epigenetic changes associated with the progression of normal prostatic glandular formation to BPH, as early as 1994 our group suggested that the presence of prostatic inflammation could be associated with pathogenesis and progression of both histological and clinical BPH. We have demonstrated that histological prostate inflammation is very common in patients with BPH as well as patients who are both symptomatic and not symptomatic. Our local research group spearheaded an international consensus classification system for prostatic inflammation that we have subsequently employed in our ongoing study of over 8,000 men undergoing 3 serial biopsies over a 4 year period of time. The MTOPS BPH study data base subanalyses of the more than 1,000 men who underwent baseline biopsies strongly suggested that prostatic inflammation appears to be the strongest and most robust predictor of symptomatic progression as well as response to drug therapy. An analyses T-cell phenotypes, cytokine expression patterns and cellular cross talk in BPH tissues of 101 BPH patients and prostatic cell cultures showed that chronic inflammation triggers histological and clinical progression. The search for urine or serum biomarkers of prostatic inflammation is highly relevant to better target therapies for men with this common condition. 