Lynne Abbess, a partner at specialist law firm Hempsons, said GPs should start thinking about the management support they might need when they take on commissioning.
Ms Abbess said the 'obvious' option is for GPs to take on PCT commissioners, but added that if they are transferred under Transfer of Undertakings (Protection of Employment) regulations (TUPE), this could create workforce and financial problems for consortia.
She said: 'It is worth taking good PCT commissioners in under TUPE. It is a positive thing to do. TUPE will apply if the consortia take over activity carried out by the local PCT.
'But GPs need to understand that TUPE operates like an act of God and they may also have to take on people that they do not want.'
Ms Abbess warned that if PCT commissioners are transferred under TUPE arrangements, GPs could be liable to pay the total employment term for that individual if they have to make them redundant later down the line.
Ms Abbess said there were other options, such as bringing in PCT staff from other areas, which could mean they were effectively new employees.
She suggested GPs could consider bringing in staff who have dealt with procurement in a different context, or using private companies that already have the skills and infrastructure.
Dr John Grenville, a GPC member, said GP consortia would be keen to retain good NHS managers. He added that the DoH could smooth the transition by making money available to consortia for them to carry the risk of having to offer large redundancy packages. But he said he was not overly optimistic this would happen.