Modern society is in the fourth industrial revolution, where artificial intelligence, big data, the Internet of Things, and machine learning drive competitiveness. A staff skill portfolio ensures sustainable growth, but rapid skill obsolescence makes traditional training ineffective, creating a gap between digital economy needs and current development systems. The study aimed to develop and substantiate an integrated model of a project-based approach to staff skill portfolio development, adapted to the dynamic conditions of digital transformation and focused on achieving measurable business results. The hypothesis was that using a project-based approach would significantly accelerate and systematise the process of developing skills, while ensuring a measurable business result. Methodology included systematic and comparative analysis and a modelling method. The comparative analysis revealed the strengths and weaknesses of Waterfall and Agile/Scrum approaches. An integrated Skill-Sprint model was developed based on synthesising their advantages. The model combined Waterfall’s strategic predictability with Agile’s tactical flexibility. The key tool was the “skill backlog”. The model’s approval at Polyemos Company confirmed the hypothesis by achieving a measurable business result: within three sprints, the employees mastered predictive analytics, which led to a 6.2% reduction in the company’s customer churn. This confirmed the Skill-Sprint Model effectiveness in accelerating skill development and achieving business results. The study’s scientific novelty lies in creating an integrated Skill-Sprint model that links strategic business goals with the operational development of skills. The practical significance lies in the possibility of using the model as a ready-made framework for building adaptive corporate training systems.