De facto states are entities that resemble normal states, except for one difference: they lack international recognition or enjoy it only to a limited extent. Scott Pegg initiated a scholarly inquiry on these entities in 1998 when he published his seminal book, International Society and the De Facto State. Counting about twenty years after the birth of de facto state studies, scholars have started publishing their reflections on the problems that these studies face and directions for future research. I follow this reflective trend in my essay, drawing on my nearly two-decade-long experience of researching de facto states. More precisely, I discuss four problems of de facto state studies and suggest how they can be solved. These problems are as follows: 1. no consensus on a definition of a de facto state, 2. imperfect existing definitions, 3. insufficient engagement with the non-Western literature, and 4. indifference to other concepts and frameworks when studying de facto states.