Voluntary group migration occurs when a collectivity reaches a group-level decision to migrate and does so as a community without external compulsion. Typical examples include collective settler movements and voluntary repatriations of refugee communities. We demonstrate the distinctive characteristics of voluntary group migration that make it hard to analyze with current migration theories, and we develop an initial theoretical framework identifying the conditions that typically produce this type of population flow. Recognizing the collective nature of the mobilization that leads to voluntary group migration, we turn to social movement theory as a source of analytical tools that, in combination with concepts offered by prior migration theories, help us build an initial theory. To illustrate our ideas, we discuss an especially revealing contemporary case: the resettlement of Crimean Tatars to their original homeland.