Consulting giant McKinsey & Company has agreed to a substantial settlement of $650 million to resolve a federal investigation regarding its role in the opioid crisis, specifically its consulting work with Purdue Pharma, the maker of OxyContin. The settlement is described as a warning to consultants about accountability in corporate practices. As part of the resolution, McKinsey has also issued an apology for its actions that contributed to the opioid epidemic. The case underscores the ongoing repercussions for companies linked to the promotion of addictive painkillers.