The Affordable Care Act has made significant changes to group health plans since it was enacted in 2010. Many of these key reforms became effective in 2014 and 2015, including health plan design changes, increased wellness program incentives and employer shared responsibility penalties. Changes to some ACA requirements, such as increased dollar limits, take effect in 2019 for employers sponsoring group health plans. To prepare for 2019, employers should review upcoming requirements and develop a compliance strategy. This article provides an overview of the employer shared responsibility rules.