Abstract: The lingusitic forms of influence used by eight life insurance salesmen were studied. Four of the salesmen were the top producers in their companies, and the other four, matched on background variables, were evaluated as "average" producers. A 45-minute long cassette recording of each salesman's work was analyzed for frequency, chronology, and style of usage of linguistic patterns of persuasion which have been previously identified in the work of master hypnotists (Bandler & Grinder, 1975, 1975a, 1979). Fourteen other highly-successful salespeople, working in real estate sales, luxury automobile sales, and investment (stocks, commodities, and trust deed) sales were studied in a less formal way for their usage of these linguistic patterns of influence. A reliability study was conducted on the coding system which was developed to analyze the 45-minute long audio tapes. The first 10 minutes of each tape was used to determine intercoder reliability. The mean number of linguistic patterns identified in each 10- minute tape segment was 574; the range was 421 to 787. The mean level of agreement between coders was 84.3 percent, using conservative scoring conventions. The level of agreement between coders ranged from 72.4 percent to 89.5 percent. In the discussion of the significance of the reliability study, additional scoring conventions are presented which are expected to raise intercoder reliability in future studies of this type. The interaction between salesperson and customer is described in terms of a cybernetic model, exhibiting feedback, redundancy, and homeostasis. The majority of the salespeople studied used almost all of the linguistic patterns of influence, but the patterns were found to be utilized in significantly different ways and at different times by the highly-successful salespeople and the less-successful salespeople. Linguistic patterns of confusion, selectional restriction violations, and linguistic patterns of suprise were used rarely by top salespeople and were almost never used by less-successful salespeople. Less-successful salespeople were found to use more comparative deletions, phrases lacking referential indices, conjunctive leading statements, opinion- pacing statements, response-potential building patterns, superlative deletions, and unspecified verbs than did highly-successful salespeople. Highly- successful salespeople were found to employ anchors and tonality shifts, attention-focusing statements, imbedded commands, adverbial leading statements, cause-effect leading statements, metaphors, mind- reading patterns, modal operators of necessity, modal operators of possibility, and statements pacing mood, objections, observables, and predicate usage with greater frequency than that shown by less-successful salespeople. Highly-successful salespeople were found to begin their sales presentations with a predominance of nonspecific language patterns. As s/he collected information on the customer, and as s/he paced the cognitive maps and experience of the world of the customer, more specific language patterns were then utilized by the successful salesperson to elicit desired responses in the customer. The findings of this study further indicate that the stronger linguistic forms of influence are utilized by top salespeople in the middle and close of the sales interaction, after they have first built rapport and trust with the customer through the use of pacing statements. Less-successful salespeople were found to maintain a high- frequency usage of nonspecific language patterns throughout the sales interaction. They were also found to use certain strong linguistic forms of influence relatively early in the sales interaction, possibly endangering rapport with the customers. Implications and significance of the findings are examined, and suggestions are presented for future research concerning how we, as human beings, understand and are influenced by certain psycholinguistic patterns of persuasion.