In the year 2000, a previous Editorial in this journal reviewed the criteria for authorship as defined by experienced authors and editors, discussed in selected references from the biomedical literature. An emphasis was given to the definition of authorship stated in the available 1997 version qf the "Uniform Requiremei its for ManuscHpts Submitted to Biomedical Journals". After that Editorial was published, an updated version of the "Uniform Requirements" established important changes in their criteria; eg. Participation of each author in the work should permit them to take public responsibility for "appropiate portions of the content"; and acquisition of data was added as an acceptable alternative in the first requisite for authorship. These and other changes should be difussed to prospective authors, particularly in multicentric studies usually leading to multiauthorship. This new Editorial and a translation into Spanish of the authorship criteria contained in an. updated (2001) version of the "Uniform Requirements" are included in this issue of Revista Medica de Chile with the purpose of stimulating authors and readers to think in their implications.