Few studies have investigated how individuals with partially intelligible speech choose to communicate, including how, when, and why they might use a speech-generating device (SGD). This study aimed to add to the literature by exploring how this group of individuals use different communication strategies. Qualitative interviews were carried out with 10 participants with partially intelligible speech with the aim of investigating participants' perceptions of modes of communication and communication strategies. Transcripts were analyzed using Framework Analysis to investigate the role of SGDs alongside other communication strategies. Factors that influence why, when, and how a person chooses to communicate were identified and these were interpreted as an explanatory model of communication with partially intelligible speech. Participants described how they made the decision whether to attempt to communicate at all and then which communication method to use. Decision-making was influenced by the importance of the message, how much time is available, past experience, and the communication partner. Each communication attempt adds to an individuals' experience of communicating and influences subsequent decisions. This study suggests that individuals with partially intelligible speech are at risk of reduced communication environments and networks and that current SGDs may not be designed in a way that recognizes their particular needs.