Help with a query

Hi, I have a table in my MySQL database called bookings: CREATE TABLE WMS_Bookings ( Booking_ID int(11) DEFAULT '' NOT NULL auto_increment, User_ID int(11) DEFAULT '0' NOT NULL , Project_ID int(11) DEFAULT '0' NOT NULL , Rep_ID int(11) DEFAULT '0' NOT NULL , PCT_ID int(11) DEFAULT '0' NOT NULL , Practice_ID int(11) DEFAULT '0' NOT NULL , Booking_Start_Date date DEFAULT '0000-00-00' NOT NULL , Booking_End_Date date DEFAULT '0000-00-00' NOT NULL , Booking_Days int(11) DEFAULT '1' NOT NULL , Booking_Hours decimal(3,2) DEFAULT '0.00' NOT NULL , Booking_Mileage int(5) , Booking_Status int(2) DEFAULT '0' NOT NULL , Work_Type varchar(20) DEFAULT '' NOT NULL , Additional_Notes text , PRIMARY KEY (Booking_ID,User_ID,Project_ID,Rep_ID,PCT_ID) ); How can i check whether a user is already booked for a given period? I have tried the following query but this only checks for a booking that starts before the gaiven date and ends after it SELECT B.* FROM WMS_User U, WMS_Bookings B WHERE B.User_ID = '1' AND B.Booking_Start_Date >= '2003-04-28' AND B.Booking_End_Date <= '2003-04-29' if a user is booked from 2003-04-29 to 2003-05-01 then the query returns no rows... Thanks for your help