Twenty two "Public Health Units" were visited and evaluated as to standards of storage recommended by the Brazilian Immunization Programme. In 86.4% of the units, refrigerators were adequately or regularly maintained. However, when items such as proper inside location of the vaccines in the refrigerator or the control of temperature were checked, only 60% and 54.5% respectively presented adequate storage conditions. In 90% of the Units health workers complained of lack of immediate technical support in emergency situations. In 100% of the vaccine samples tilers were well under the minimal recommended potency. Inadequacy and lack of uniformity, at regional and local levels, concerning conditions of vaccine storage as well as insufficient training of health personnel must have contributed to the above results.