Crown Business Communications won the business following a competitive pitch and is set to produce an initial conference in London in the middle of April.
Around 100 senior-level delegates will attend the event, which will also include a gala dinner. Crown Business Communications will provide production, venue finding and logistics support.
Sales and marketing director Simon Hambley said: "The conference is for Microsoft to communicate its cloud computing strategy to its EMEA partners. This is a big deal for Microsoft; it also shows we can attract clients in the top-ten brands globally."
Crown Business Communications has set up a dedicated Microsoft account team of three staff to deal with the work in the coming year.
An experiential campaign around the launch of the Microsoft Windows 7 phone is part of the contract, as is the World Hosting Days exhibition from 22-25 March in Germany.