for this Collection is to highlight a poten- tially common depression subtype, named tentatively ‘‘stress-induced depression’’ (STRID), recently described in Sweden by A˚sberg and coworkers [71]. A dramatic increase in the number of workers on long- term sick leave was observed between the years 1997 and 2003 (Statistics Sweden, 2004; http://www.scb.se). Studies of con- secutive cases with psychiatric diagnoses culled from the databases of two large Swedish insurance companies showed that about 80% of patients met DSM-IV criteria for MD ( A˚sberg et al., unpublished data). The depression episodes were mild to moderate (MADRS ,20), and accom- panied by significant working memory impairment [71]. Follow up showed that STRID tended to have a prolonged course, and that the patients often re- mained in a state of exhaustion after the depressive symptoms had remitted. 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