The aim of the current quasi-experimental field study was to investigate the immediate and 3-month follow-up effects of the resilience-building program ResilienceWise, using a 2 (group) × 3 (time) mixed design. This blended program consisted of an individual assessment, four one-on-one sessions, and two modules in the online, self-help, psychological fitness program Psyfit (Bolier et al., 2013). The aim was to enhance resilience resources and positive adaptation in health-care office workers (n = 91) of a large Dutch insurance company during organizational change. The results of this experimental group were compared with the results of a no-program comparison group (n = 140). Positive immediate and long-term effects were found on hope, self-efficacy, environmental mastery, purpose in life, positive affect, positive relationships, general health, and recovery from stress. Only a long-term effect was found on task performance. No effects were found on optimism and mindfulness. The strength of the coach–client relationship was related to most of the immediate program effects. This article reports additional results for a group that attended all one-on-one sessions but did not (fully) adhere to the online component of the ResilienceWise program (n = 67). For this group, we found no significant effects on the dependent variables, implying that only the complete ResilienceWise program was effective. All in all, the current study confirms that resilience resources and positive adaptation can be enhanced in employees during organizational change. These findings extend the existing evidence that resilience-building programs can be effective and are promising for employees in need of resilience during organizational change. (PsycInfo Database Record (c) 2022 APA, all rights reserved)