His research interests include chronic renal insufficiency, hypertension, transplant, and diabetic nephropathy. He has participated in a number controlled trials, including the African-American Study of Kidney Disease and Hypertension (AASK) and the RENAAL Study. He is currently a Co-Investigator for the AASK Cohort Study and a Principal Investigator for the Chronic Renal Insufficiency Cohort (CRIC) Study. Dr Lash has received research funds from Merck Research Labs.