Freely produced speech is a common source of data for speech research. This article is an introduction to this thematic volume and discusses freely produced speech from different perspectives. Freely produced speech is often seen as the opposite of controlled, often phonetic experiments in laboratory conditions. However, it is very difficult to determine which data collection methods are sufficient for freely produced speech to be considered authentic and natural. The topics of the articles included vary from dialectological research in Finland and the phonetic features of Namibian English to second language fluency studies as well as proficiency or speaker assessments in a second language. As this thematic issue will show, it is essential to conduct research on freely produced speech in a comprehensive way, as well as to understand the importance of the results obtained. The way freely produced speech is assessed can have a significant impact on an individual’s life, for example, in gatekeeper evaluations.