The three conditions given in the literature for the pervasiveness of linguistic insecurity (a speaker's attitude toward his or her own speech revealed in face to face interaction through the upward or downward shift of language forms) exist in the case of speakers of the Spanish vernacular of Puerto Rico. The conditions are: the rise of a middle class, a fossilized language curriculum, and a dialect stereotyped as inferior. A study of the latent attitudes of insecurity manifested by 104 teachers and students in 3 public high schools on the island assessed such factors as the following: the perceived social status of the students and teachers; student attitudes toward teachers as linguistic role models; attitudes about correctness and the tendency towards hypercorrection; and the prestige of language variaties spoken by various social, occupational, and national groups, including the subjects' own. The survey found the subjects to be generally insecure, particularly at the lexical level of language structure. No significant interaction of the linguistic variables related to linguistic insecurity occurred between or within the subject groups, although they showed a defensive ethnic stance about their linguistic insecurity. (Author/MSE)