In computer science and related disciplines, "considered harmful" is a phrase popularly used in the titles of diatribes and other critical essays. It originates with Edsger W. Dijkstra's letter "Go To Statement Considered Harmful", published in the March 1968 Communications of the ACM, in which he criticized the excessive use of the GOTO statement in the programming languages of the day and advocated structured programming instead. Structured programming is not as widely debated in contemporary computer science, but the pithy and adaptable phrase "X considered harmful" (actually the invention of the ACM editor Niklaus Wirth, and not Dijkstra) continues to be used to indicate that an article contains controversial and strongly asserted views.

An opponent of Dijkstra's paper wrote a paper shortly afterwards, titled "'Go To Considered Harmful' Considered Harmful".

Many persons use the "[something] considered harmful" titling as a joke, such as "Sex considered harmful" or "Internet Explorer considered harmful".

Some variants with replacement adjectives ("considered silly", etc.) have been noted in hacker jargon. [1] The phrase is also occasionally capitalized for effect.