Alvaro Morales has advanced the field of urology, notably in the areas of oncology and andrology. He is best known for spearheading the use of Bacillus Calmette-Guérin (BCG) as a bladder cancer treatment in the 1970s; he has also advanced the knowledge of testosterone deficiency. At Queen's University, he headed the Department of Urology for 15 years, and is the founding director of the Centre of Applied Urological Research.