The 44-year-old was previously in the role for 18 months
Frank Lampard says it's his aim to get the squad showing a "passion" to play for Chelsea between now and the end of the season.
The club legend is back in charge for a second spell as manager in a caretaker role, following last weekend's sacking of Graham Potter.
The 44-year-old was previously in the role for 18 months in the job before being sacked in January 2021.
Co-controlling owners Todd Boehly and Behdad Eghbali said: "We are delighted to welcome Frank back to Stamford Bridge. Frank is a Premier League Hall of Famer and a legend at this club.
"As we continue our thorough and exhaustive process for a permanent head coach, we want to provide the club and our fans with a clear and stable plan for the remainder of the season.
"We want to give ourselves every chance of success and Frank has all of the characteristics and qualities we need to drive us to the finish line.
'We have an important game against Wolves on Saturday and then we will turn our attention to our Champions League quarter-final in Madrid next week.
"We are all going to give Frank our full backing as we aim to get the best possible outcome from all our remaining games," they added.
Lampard insists he'll be trying to keep his message simple:

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