Pain or abdominal discomfort are recurrent symptoms in Irritable Bowel Syndrome and one of the symptoms used for its diagnosis. The present text characterizes this syndrome emphasizing aspects related with pain and presents some forms of intervention used for its control. The paper also presents a set of variables found to be associated with the symptoms in IBS and a case study exemplifying the use of functional analysis to identify these variables. Despite being topographically used as a symptoms' criterion, pain requires a careful functional analysis in order to be correctly understood and, consequently, it cannot be treated with topic interventions, but with systemic interventions which address the focus to the variables matrixes from which this pain results.