Since their creation, the number of mental health helplines in operation have risen dramatically. Varying by organisation, helplines are staffed by telephone support workers (TSWs) who are either volunteers, professionals and/or paraprofessionals. Evidence suggests that helplines are an effective source of support, but TSWs are exposed to several unique stressors that can lead to both positive and negative outcomes. Studies on TSWs have explored several outcomes ranging from burnout and vicarious trauma to vicarious post-traumatic growth and compassion satisfaction. Despite this, there is a limited understanding of the pathway to impairment for TSWs and there is a paucity of research on the positive consequences. Moreover, research has primarily focused on volunteer TSWs rather than paraprofessionals. Paraprofessionals, however, may be more at risk due to their increased exposure to the stressors of the TSW role. Using a qualitative approach and guided by a Critical Realist methodology, the current study utilised semi-structured interviews to explore and examine the experiences of paraprofessional TSWs at the New Zealand National Telehealth Service. Data were analysed using thematic analysis. Results indicated that TSWs experience a range of outcomes, such as enhanced confidence, greater resilience, improved self-worth, along with feelings of inadequacy or thoughts of self-doubt, a fluctuating ability to empathise and elements of uncertainty. TSWs are prone to exhaustion that may be increased by personal and corporate processes, which can impact their ability to empathise and influences the depersonalisation of callers. Although they have a strong desire to support their callers, TSWs recognise that some callers require support that is beyond the scope of the service and/or the training of the TSW, which can contribute to feelings of helplessness or thoughts of inadequacies. Findings are discussed in terms of the support requirements of TSWs, such as the management of uncertainty by drawing on the concept of wisdom.