This research reports on the development of a combined measure of Psychological Capital and Mindfulness (PsyCap-M), that facilitate leaders’ affectivity at work, tested on a daily basis. PsyCap is one’s positive psychological state of development (self-efficacy, optimism, hope and resilience), while Mindfulness refers to awareness and attention to the present moment, non-judgmentally, enabling individuals to be less reactive. Data is from 400 organizations across New Zealand. Survey 1 contained PsyCap and mindfulness plus four (daily) surveys containing positive and negative affect were completed.222 completed surveys were analyzed. We confirmed the PsyCap-M measure using CFA in AMOS. Towards our affectivity outcomes (positive affect and negative affect), we tested two models: (1) PsyCap and mindfulness separately, then (2) combined as a PsyCap-M, to determine whether the combined construct was a stronger predictor than either alone. Overall, this analysis supported a higher order model with five-factors: hope, efficacy, resilience, optimism and mindfulness (PsyCap-M). Findings were that PsyCap alone is the dominant predictor of positive affect (positive influence), while mindfulness alone if the dominant (negative) predictor of negative affect. However, in both models the PsyCap-M is a stronger predictor and accounts for more variance than when PsyCap and Mindfulness are entered as separate constructs.