Despite a reputation in some quarters for irrationality, Pentecostal theology and practice is rational in a variety of ways. Major proponents of Pentecostal theology show themselves to value reason while churches, in their sermons and documents, embody rational argument. In the same way Pentecostal denominations also organise themselves rationally and accept reasoned debate in their conferences. Yet there is an openness to experience and to the Spirit in Pentecostalism which can seem irrational which is why the cognitive process of discernment is explicitly welcomed. Beyond this, Pentecostal theology, especially in its interdisciplinary and practical forms, can and does use empirical information gathered by social science methods about the dynamics of Pentecostal and charismatic congregations. Equally it can welcome data from psychological studies.