The aim of this study was to identify the characteristics and use of expert know-how in agricultural planning on large-scale paddy field farms and to develop guidelines for cultivating employees' capabilities in corporate farms. This case study was conducted on a corporate farm in Shiga Prefecture. The results indicate that a high level of knowledge and a variety of technical skills are required for agricultural planning. These skills include the ability to manage the knowledge, both general and technical, required to conduct agricultural operations and flexibly deploy knowledge and skills under a variety of circumstances. Furthermore, we found that the skills were primarily based on two types of intellectual management skills that can be broadly categorized as either decided type or predicted type depending on the nature of the decision made. In addition, decision-making requires the technical ability to make use of comprehensive sets of factors relating to knowledge, skills, and data. We also observed a low acquisition rate of management skills in terms of both specific technical and more general intellectual activities among non-experts. Implementation of the following four initiatives could help to improve the cultivation of employee capabilities: (1) systematic organizational methods of formulating semi-tacit knowledge, such as the management of particular types of knowledge; (2) actions to support a better understanding of the overall factors required for decision-making using intellectual management skills; (3) actions to support the employees' ability to predict changes using intellectual management skills; and (4) practical on-the-job training and systematic labor management techniques.