This IDC study presents forecasts of spending (customer expenditures) for the offshore-based horizontal BPO services market for 2017–2021 that includes HR, finance and accounting, procurement, and customer care by four importing regions (United States, Canada, EMEA, APAC). This study includes advice to providers of BPO services, an analysis of key market and industry trends by the importing market, key market drivers and inhibitors, significant market developments, and highlights of key changes from the prior forecast. This study also updates the previous forecast published in Worldwide Offshore-Based Horizontal BPO Services Forecast, 2016–2020 (IDC #US40787516, November 2016)."The offshore BPO services market is facing increasing challenges driven by geopolitical instability, customer shift to new service models (e.g., cloud), and increasing pressure to automate labor processes, all of which will require making fundamental changes to their businesses," says David Tapper, vice president, Outsourcing and Managed Cloud Services at IDC. "Key areas of focus that will enable offshore BPO providers to maintain a competitive edge must include offering more business advisory services, developing comprehensive AI strategy and investments, investing in local talent, going beyond the basics for analytics, and developing strategic KPIs to benchmark against disruptive models."