2020, Kay Naumann, Jana Bowden and Mark Gabbott. Purpose: The purpose of this study is to operationalise and measure the effects of negative customer engagement (CE) in conjunction with positive CE. Both valences are explored through affective, cognitive and behaviour dimensions, and, in relation to the antecedent of involvement and outcome of word-of-mouth (WOM). It also explores the moderating influence of service context by examining engagement within a social service versus a social networking site (SNS). Engagement with the dual focal objects of a service brand and a service community are also examined. Design/methodology/approach: Structural equation modelling is used to analyse 625 survey responses. Findings: Involvement is a strong driver of positive CE, and positive CE has a strong effect on WOM. These findings are consistent across the "brand" and "community" object, suggesting positive CE is mutually reinforced by different objects in a relationship. Positive CE is also found to operate consistently across the service types. Involvement is a moderately negative driver of negative CE, and negative CE is a positive driver of WOM. These relationships operate differently across the objects and service types. Involvement has a stronger inverse effect on negative CE for the social service, diverging from assumptions that negative CE is reflective of highly involved customers. Interestingly, negative CE has a stronger effect on WOM in the social service, highlighting the active and vocal nature of customers within this service context. Originality/value: To the best of the authors' knowledge, this is the first paper to quantitatively measure positive and negative valences of engagement concurrently, and examine the moderating effect of dual objects across contrasting service types.