Have each person in the group choose a potential destination, and research it. At a meeting when you are all together, have everyone give a presentation. People can talk about what there is to do in the destination, costs involved, and accommodations. This way your group will be able to make an informed decision about where to travel. You may also find that a consensus emerges, making selection of a destination easier.
Have each member of the travel party bring a brochure from a travel agent. You can then spend time looking through these brochures getting holiday ideas. As you pass round the brochures you can discuss the merits of each, and you will soon agree on a consensus. If you do not, then you can at least rule out some possibilities for travel destinations. Host another bring-a-brochure party if the first one didn't work.
If you are dispersed over a large area, or each member of the group has work commitments that allows you little free time, then use an online resource to help you plan your destination. Sites such as Group Travel Planner, Travel Group Planner and Triporama all allow you to create a space online where you can select dates of travel and research destinations without having to meet face to face. This may be the only viable option in many cases.
If you are planning group travel for a large group, your financial weight will give you more power. Ask a travel agent to prepare a few ideas for your travel, and to give a short presentation at a group meeting. He will make a case for each destination and tell you what discounts you will be able to get as a group. At the end of the meeting, you can ask him questions, and vote on a travel plan.
