At VNIIEF laser fusion investigations are based on photodissociation iodine lasers (the wavelength of radiation (lambda) equals 1.315 micrometers ). The main goals of the investigations are determination of ignition conditions, choice of target types, laser interaction regime, energy and other necessary characteristics. Beginning in 1980 we conducted experiments on irradiation of targets of different types on the one-channel four-beam facility ISKRA-4 producing 10 TW. In the last years ISKRA-4 was upgraded: we realized conversion to the second harmonic and introduced the eight-beam irradiation system. Experiments at the second harmonic yielded 1 kJ of energy and 3 TW of power. In 1989 we built and put into operation the 12-channel facility ISKRA-5 producing energy up to 30 kJ and power up to 120 TW. In 1990 we began a series of target irradiation experiments on this facility. The present work is a review of laser fusion investigations conducted on the facilities ISKRA-4 and ISKRA-5. It contains a brief description of the facilities and of some specific phenomena which occur during monopulse amplification in high-power iodine lasers. Considerable attention is paid to problems of direct-drive targets and experimental results obtained on ISKRA-4 which are given in comparison with the data of model calculations. The work is concluded with the results of first experiments on irradiation of targets with a reversed corona which were conducted on the facility ISKRA-5.