Caring alters plans to return to work and changes career trajectories for many primary caregivers of children with disabilities, most of whom are mothers. The Juggling Work & Care study was a South Australian cross-sectional mail-out and online survey for carers of children and young adults with developmental disabilities aged 0–25 years, which investigated work participation, work–life balance and psychological well-being. This study shows that mothers who were in a couple relationship and primary caregivers for their child (n = 287) were less likely to be in paid employment and worked fewer hours than mothers in the general population, regardless of age of child. Work participation was shown to be strongly related to the severity of child disability. Impacts of caring for mothers were significant. Over a quarter of mothers who had intended to work after the birth of their child had not done so. As well, many mothers who had returned to work reported reduced job opportunities and career progression. Of concern, 9 out of 10 mothers were unaware of their right to request a change in working arrangements to assist them to care. Changes in workplace support for carers, for example, awareness of legislation and flexible leave entitlements, as well as increased community supports such as appropriate and accessible (child)care, could improve the financial and social circumstances of families and result in significant benefits to Australia's economy.