The phrase "smooth handover" means transferring something to another person or group in a comfortable and seamless way, without any problems or disruptions. Full definition
Firms making redundancies run the risk of stress - related mistakes, and not having smooth handovers of ongoing matters, perhaps leaving loose ends such as registration of mortgages. (newlawjournal.co.uk)
5) Smooth handover of clients and candidates: Co-operate in a handover of your current orders, your clients and your hot talent. (careerdigital.com)
He will remain on the board until after the general election in May to ensure a smooth handover when a new government is elected. (theguardian.com)