Employees' sense of development is an essential component of their well-being that enhances their work performance. In the Japanese higher education sector, the number of foreign academics has increased considerably due to the strong backing of government initiatives. Although studies have unpacked foreign academics' intercultural challenges and marginalisation experiences, their developmental experiences in host countries have been under-researched. Thus, this mixed-methods study examined what explains foreign early career academics' sense of knowledge and intellectual development and how. Both the quantitative and qualitative results indicated collegiality's key role in their development, while the discrepancies between them suggest that their development is better explained by how knowledge is transmitted via three key conditions--access, interpersonal matters and sources--than workplace conditions. Foreign academics' perspectives can contribute to institutional policy development, because they may be aware of the status quo to which locals feel resigned.