Orally disintegrating tablets (ODTs) are attractive oral solid dosage forms as it has significant impact on the patient compliance. ODTs disintegrate and/or dissolve rapidly in the saliva without the need for water and offer an advantage for populations who have difficulty in swallowing. There seems to be lack of a standardized system to characterize ODTs. Evaluation of ODTs can be done by friability, hardness, wetting time, water absorption ratio, in vitro disintegration test and dissolution test. The current article summarizes in vitro quality control tests and clinical studies for ODTs.