The development of an easily-administered, valid and reliable meta-motivational state measure, capable of assessing the full spectrum of states, is needed to further the understanding and application of reversal theory (Apter, 2013). The present paper outlines an adaptation of the Stroop protocol to implicitly measure meta-motivational states and two subsequent validation studies. Consistent with Stroop principles, we hypothesised that state congruent stimuli would capture individuals’ attention causing an increased response latency (e.g., Ayres & Sonandre, 2002). Study one (n = 68) assessed the concurrent validity of the Meta-Motivational Stroop task (MMS) against two widely-used explicit measures of state, the Telic/Paratelic State Inventory (T/PSI; O’Connell & Calhoun, 2001) and the State of Mind Indicator for Athletes (SOMIFA; Kerr & Apter, 1999). Contrary to expectations, emotionally incongruent stimuli caused a delayed response, interpreted as an interference effect (Rothermund, 2003). Study two (n = 30) manipulated state, through expressive writing and imagery, to assess the ability of the Stroop task to detect changes in state. Results offered some support for the interference effect, with incongruent stimuli resulting in an increased response latency when writing from a telic perspective. Taken together, results suggest an implicit measure of meta-motivational state has some promise, particularly given the observed limitations of explicit measures.