To add people from your business to the trip, go to the people tab and click add people.
Start typing the name/email address of the business traveller and their name will appear. If their name does not appear, they may not have a Travaplan account for your business. You can set up an account for them by going to "Create an account"
Click on the circle to the right of their name and click "add person(s)
You can now Search for flights and Search for accommodation.