The widespread and continued growth of mobile telephony within society means that protocols regarding acceptable public use are being continually redefined. In order to understand the different needs and motivations of mobile phone users and to assist with the development of effective policy, it is important first to consider the phone-related behaviours with which people are comfortable and those with which they become annoyed. A survey of 184 young adults was undertaken to explore the relationships between their comfort making and receiving mobile phone calls in different social contexts, their affective responses to public mobile phone use by others, and how such factors relate to key personal attributes and specific beliefs regarding calling behaviour. Mobile phone users differed in the extent to which they felt comfortable making and receiving calls in different social contexts and were less annoyed by others using mobile phones in locations where they themselves felt most comfortable making calls. Three important influences which predicted behavioural measures of phone use were found to be views regarding the application of public restrictions, desire to remain personally contactable and ‘social usability’ or anxiety regarding phone use in the presence of others. User personality and individual attributes such as age and gender were also found to be differentially associated with some aspects of phone-related behaviours.