Book Attendance 
This function lets you enroll attendees for business events and, at the same time, store the relevant billing and activity allocation data (settlement type, fees, and so on).
For billing:
Integration between Training & Event Management and Sales is active, and all settings relevant for billing have been made.
An address for the attendee must be available.
The customer master record is in the sales area of the business event. If not, then you should have created a one-time customer and stored address data for the attendee there.
For internal activity allocation:
Integration between Training and Event Management and Cost Accounting is active and all of the settings relevant for activity allocation have been made.
The attendee’s cost center assignment is maintained.
The receiver cost center and sender cost center and/or all account assignment objects (cost center/order/WBS element or project) are maintained and are in the same controlling area.
The activity type for event attendance must be maintained.
You can make bookings for planned and firmly booked events, both internal and external. You cannot make bookings for business events that are canceled, locked, or that have a historical record flag.
You can make single bookings for individual attendees (person, user, external person, applicant, or contact person) and group bookings for group attendees (company, organizational unit, customer or interested party).
You can make list bookings. With the list booking function, you can book multiple attendees simultaneously for one event, or one attendee for a number of different events at one go.
You can create attendees or additional attendee data when booking.
When you book attendees, you enter all of the relevant billing and activity allocation data that is later required for settling attendance fees.
You have the option of automatically transferring the settlement data stored for the corresponding attendee type to which the attendee belongs.

In this case, the billing and allocation data, such as cost center assignment, that is stored for the attendee type (in Customizing for Training and Event Management under Day-to-Day Activities ® Booking ® Specify Attendee Type Control) is transferred to the attendee you are booking.
Alternatively, you can change the specifications made for the attendee type or make additional specifications and create notes for a given attendee. You do so in the dialog box that appears when you choose Book/Payment Info.

If you want to settle attendance fees by credit card, specify different partner functions for billing, or distribute costs to multiple account assignment objects in activity allocation, you must choose Book/Payment Info since this function offers you a dialog box in which to enter this data.
Any waiting-list bookings for firmly booked events of this type are canceled.
Any prebookings of an attendee for the business event type are deleted.
The number of business event attendees is automatically updated.
Bookings are automatically assigned the same status as the business event for which they are made.
If integration with Time Management is active, the relevant attendance records in Time Management are updated when the attendee type Person is booked.
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1. You select a business event by entering a time period and a business event type or alternatively, in the dynamic attendance menu by selecting the required business event.
2. You enter the attendee you want to book. You can create attendees that do not already exist in the system or change attendee data when you execute the Book function.
3. You specify the booking priority. The booking priority specifies whether an attendee gets a place on the attendee list or not. When a booking is made, the system carries out a capacity check to see how many attendees may be booked for the business event. The following restrictions apply:
Once optimum capacity has been reached, only bookings with essential priority are possible.
Once maximum capacity has been reached, only bookings on the waiting list are possible.
See also: Booking Priority
4. You choose Book/Payment Info and, in the Fee and Assignment dialog box, enter the relevant settlement data and, where relevant create notes for the transaction. Alternatively, you simply choose Book.
5. Attendee checks are performed. The system checks whether the attendee is available in the business event period. This check is carried out for all attendee types. Further specific checks are carried out for individual and group bookings, such as checks to ensure that an attendee is not booked for another event at the same time. Depending on the result of the check, the following occurs:
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a. The attendee is automatically booked for the event.
b. You can book the attendee even if an information message or a warning message is displayed.
c. You cannot book the attendee if an error message is displayed.
See also:
Booking Multiple Attendees for a Business Event
Booking an Attendee for Multiple Business Events