The concept of reciprocity permeates the literature on campus-community partnership as a matter of principle, aspiration, and--ideally--best practice. More recently, principles and practices of sustainability have pervaded scholarly and popular discourse, emerging from and applying to environmental studies, economic development, and social justice fields, with aspirations to extend well beyond. This article explores the relationship between principles of reciprocity in community engagement scholarship and practice, and this burgeoning discourse of sustainability. The paper draws upon efforts to explore reciprocity and sustainability among community-based learning offices in the Five College Consortium and organizations in the City of Holyoke in Western Massachusetts. A theoretical frame for sustainability in campus-community partnership is proposed, linked to the delivery of reciprocity. Prominent challenges to implementing sustainability in community engagement are then considered.