Knowledge workers build their career capital through learning experiences throughout their careers. How this occurs for the R&D knowledge worker has not been previously documented. The loss of key R&D personnel in the hightechnology (high-tech) industry contributes to a loss of tacit knowledge and increased costs. A greater understanding of why and how career capital is accumulated by R&D knowledge workers will facilitate the design of career management practices that could reduce voluntary employee turnover. A qualitative investigation into the applicability of eight widely recognised career capital components revealed a new component that is relevant to the high-tech R&D environment. These applicable career capital components and associated accumulation methods were used to build a quantitative questionnaire that measured the perceptions of 59 knowledge workers in the R&D environment. This research has, for the first time, explicitly defined tangible career capital constructs that are relevant to knowledge workers in the high-tech R&D environment. The findings have been used to develop a model to help organisations understand the career needs of the R&D knowledge worker within the context of the business environment. Recommendations are presented to allow organisations and R&D knowledge workers to leverage off this research.