Spectroscopic and photometric observations of SN 1987A - IV. Days 260-385.

Spectroscopic and photometric [UBV(RI)_c_JHKLM] observations of SN 1987A in the Large Magellanic Cloud are described and briefly discussed. These cover the interval from days 260-355 after core collapse. During this period the bolometric light curve, determined from optical and infrared photometry, has been declining slightly faster than the rate expected for the radioactive decay of ^56^Co. The flux deficit is, however, compensated for by γ-radiation, indicating that the decay of ^56^Co continues to be the sole significant energy source for the supernova.