Death certificates are an important source of information for cancer registries that help to improve completenessof case finding. In many countries where routine mortality data are considered of poor quality, this source is oftenregarded as being of little value. We evaluated the contribution of death certificates to the total number of registrationsin the years 1993-1997, in the Manila Cancer Registry (MCR). We compared the “standard” practice of retrievingclinical information if the death certificate was completed in a hospital, with active search of additional informationfrom the deceased's relatives when the death was certified at home.The standard procedure allowed us to reduce theproportion of cases registered from a death certificate by 5%. The improvement varied significantly among the mostcommon sites with a reduction of 10% for lymphomas to less than 1% for cancers of the cervix.The proportion ofliver cancers registered from a death certificate only (DCO), originally 47%, was reduced to 29% by contactingrelatives of the deceased patients. In countries with limited investment in information systems, death certificates,even when recognised as being of poor quality, are an important source of information for cancer registries.