The analysis of the factor of synchronization derives specific characteristics of successful communication for relationship building in executive coaching. Additionally, based on empirical evidence regarding the effects and roles of horses, a theoretically grounded foundation for horse-assisted coaching is established. In this setting, synchronization must succeed not only in the dyad but also in the triad. Case studies illustrate how synchronization arises emotionally-intuitively and consciously-methodically between coach and coachee. Both harmony and crises play a crucial role in this process. The research findings lead to recommendations for the training and further education of coaches regarding communication, relationship building, and the use of horses.