Multiple system reforms in Australia, including the National Disability Insurance Scheme (NDIS), are changing mental health (MH) and disability-related service provision, whilst policy drivers continue to require service integration. This has necessitated service providers discovering new ways of working collaboratively to achieve an integrated model of care. This qualitative study examined what does and does not work to support collaborative and coordinated care (CCC), as essential components of service integration. The study sample (n = 59) included four cohorts: health and community service leaders (n = 16), staff (n = 23); MH service consumers with complex needs (n = 10), and MH carers (n = 10). Thematic analysis from interviews was applied to data from each cohort to identify overarching themes that described the lived experience of current CCC delivery. COREQ and EQUATOR guidelines were applied to reporting the findings. Themes emphasized CCC is enabled by the development and sustainability of positive working relationships, and depth of knowledge across health and community services. Unnavigable service systems, stigmatization, perceived power differentials, multiple and rapid service reforms and Fee-For-Service (FFS) models provide significant barriers to CCC. Recommendations include the need for accessible service navigation, consumer-friendly service environments, a stable workforce, standardization of knowledge across sectors, outcome measures and funding attached to CCC as part of a raft of potential changes.