In the last decade, there has been a sharp increase in the employment of working mothers in the South African labour market. Work-family scholars argue that organisations must develop supporting policies and benefits to shield working mothers against work-family pressures. This article focuses on the development of the Work-Family Pressure and Support Questionnaire (W-FPSQ) as a measure to assess the pressures that working mothers experience and to identify the resources they need to balance their work and family life. A sequential mixed method design was adopted to gather the data needed to develop the questionnaire. Exploratory factor analysis and correlation designs were used to explore the internal structure of the questionnaire, as well as its validity and reliability. A total of 205 mothers occupying management and professional positions were involved in the validation of the questionnaire. A six-factor measurement model was established with good to excellent factor scores; it has very satisfactory Cronbach alpha coefficients. The individual scales were labelled, Work-family pressure, Personal development, Management support, Organisational flexibility, Time for family interaction, and Child care support. The W-FPSQ provides researchers and practitioners with a tool to evaluate working mothers' experiences in balancing work and family responsibilities, and to examine the extent to which organisations are perceived as supportive of work and family. Furthermore, the W-FPSQ can be used to generate information that management needs to develop and implement workand family-supportive policies to help working mothers to balance work and family demands.