Voluntourism involves the participant providing free work to enhance their touristic experience, and often involves a “Pay to volunteer” fee. It’s typically designed around the desires of the tourist, rather than the real needs of the community itself - and as a result can end up creating more harm than good.
Unlike voluntourism, Experteering is a proven way to create lasting change. You can think of Experteering as a specific type of volunteering that is skills-based, where the goal is to transfer knowledge and specific professional expertise to help the host organization lay the foundation for long-term growth, rather than solving a specific problem.
You can view a full, detailed breakdown of the differences between Experteering and Voluntourism here.