Beam-beam experience at KEKB

KEKB has achieved the peak luminosity of 4.1 x 10{sup 33} cm{sup -2} sec{sup -1} and the present capability for delivering integrated luminosity is 224 pb{sup -1}/day. This paper describes (1) the recent performance and the problems of KEKB and (2) the comparison of beam-beam simulations with experiments at KEKB.