There is growing empirical support for the benefits of developing psychological capital (PsyCap), and the effectiveness of PsyCap interventions (PCIs) in the workplace. However, to-date, PCI delivery modes have not been compared. The first study in this article compares a face-to-face to an online PCI. The second study compares an online PCI to a micro-learning PCI utilizing a mobile application. Results from 228 participants assessed three times (before, immediately after, and six weeks after PCI completion) support the effectiveness and comparability of the three delivery modes, but also highlight notable advantages for online and micro-learning.