Controlling access to the Internet by means of filtering softwarehas become a growth industry in the U.S. and elsewhere. Its usehas increased as the mandatory response to the current plagues ofsociety, namely, pornography, violence, hate, and in general,anything seen to be unpleasant or threatening. Also of potentialconcern is the possible limitation of access to Web sites thatdiscuss drugs, without distinguishing advocacy from scientificand informed analysis of addiction. With the rise of an effectivecreationist movement dedicated to the elimination of evolutionarytheory in (...) the curriculum, it is to be expected that attempts willbe made to limit access to sites presenting such theories, incertain jurisdictions in the U.S. The current preferred method ofchoice to limit access is to filter content either by blockingaccess to specific Web sites, referred to by their URLs, or byusing a large set of keywords to prevent accessing sites thatcontain one or more of these words. Another more insidious schemeis to encourage or even require every Web site to rate itscontent along a number of dimensions, including violence,language, sexual explicitness, and nudity. Then individualbrowsers can be programmed to return references only to thosesites that fall below a pre-specified profile. The dangers forfree speech inherent in such schemes will be discussed. Effortsto produce legislation in the U.S. to mandate the use offiltering or rating programs will be described, as will somerecent court decisions involving their use in libraries. (shrink)