On March 1990 he joined the editorial team of ComputerWorld, assuming the responsibility for the international section. On September 1991 he was named Editor in Chief of ComputerWorld, a job he is occupying at present. On February 1994 he become also the Editor in Chief of Diario Informático, a daily IT publication of the IDG Communications Group in Spain.

On February 1998 he assumed the Editorial Direction of IDG Communications Spain, with responsibility for the editorial strategy of all the publications of the company in Spain (ComputerWorld, PC World, iWorld, Macworld, Dealer World, Communications World, Diario Informático) as well as for the Internet presence of IDG in Spain (www.idg.es).

He has intervened in representation of ComputerWorld in various domestic and international forums, and has contributed with his articles in the newspaper media, including the daily "EL PAIS", Antena 3 Televisión and Onda Cero Radio.

As Editor in Chief of ComputerWorld, Carlos de la Iglesia has received the SIMO Prize of Journalism of 1991, and the prize Onda Cero 1993 for the "divulgation of data processing", as well as the "Chairman´s Achiever" prize for the best editorial team among the more than 200 teams forming the Editorial Group of IDG Communications worldwide, and the National Prize for the Best Communication Work, granted by the Sociedad Española de Informática y Salud.