This article attempts to clarify the interrelationships of the so-called mixed odontogenic tumors. The difficulty in distinguishing histologically between the ameloblastic fibroma and the ameloblastic fibro-odontoma on the one hand and the developing odontoma on the other is emphasized. Also discussed is the desirability of discarding some terms used for histologic variants of ameloblastic fibroma, such as immature dentinoma and ameloblastic fibrodentinoma.