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Waikiki is an internationally recognized tourist destination and a major source of economic activity in Hawaii. Erosion is a constant threat to Waikiki's beaches and coastal properties. This applied study presents an assessment and comparison of three erosion management approaches – beach nourishment, armoring and managed retreat – in the context of Waikiki. A geographic information system (GIS) is used to project erosion rates to 2050 and 2100, while approximating effects of sea level rise (SLR). The spatial extent of erosion and costs of each management approach are estimated. Suitability of each approach is evaluated based on management impacts to economy, environment, recreation, storm protection, and resources. This framework provides a comparative analysis that can be replicated in similar settings. The findings indicate that nourishment may be a beneficial and economical approach to manage erosion in this densely developed, economically significant beach setting. Nourishment costs are on the same order of magnitude as armoring, while retreat costs are an order of magnitude higher. The larger indirect impacts and economic losses associated with armoring (beach loss) and retreat (property loss) make nourishment the least impactful option for addressing erosion in Waikiki. As the projections and understanding of climate change impacts improve, solutions may evolve. Nourishment may provide a no-regrets, suitable approach for managing erosion in Waikiki until other solutions emerge. This paper presents opportunities and implications of nourishment for planning and future research in Waikiki.