Mueller's practice will center on "high-profile investigations and crisis management," the multi-national law firm said in a press release.
The former FBI director was a partner at the firm since 2014, before the Russia probe, and worked at WilmerHale's predecessor firm for two years in the early '90s. Two other special counsel investigators, James Quarles and Aaron Zebley, are also rejoining the firm.
Mueller's investigation, spurred by the firing of then FBI Director James Comey, dominated all corners of Washington for nearly two years. A flurry of reports about President Donald Trump's communications with the president of Ukraine and subsequent launch of a formal House impeachment inquiry, however, has overshadowed coverage of the Russia investigation in recent weeks.
The special counsel confirmed the intelligence community's prior assessments that the Russian government systematically interfered in the 2016 election, but did not establish coordination between the Trump campaign and the Kremlin. 34 people were indicted in the wake of the probe, including the president's former campaign manager, Paul Manafort, and National Security Advisor Michael Flynn.