challenges. Management tasks are usually broken down into the areas of physician targeting, sales force size and structure, sales force optimization, call planning, and sales forces effectiveness. A few pharmaceutical companies have realized that training sales representatives on high science alone is not enough, especially when most products are similar in quality. Thus, training sales representatives on relationship selling techniques in addition to medical science and product knowledge, can make a difference in sales force effectiveness. Specialist physicians are relying more and more on specialty sales reps for product information, because they are more knowledgeable than primary care reps. The United States has 81,000 pharmaceutical representatives or 1 for every 7.9 physicians. The number and persistence of pharmaceutical representatives has placed a burden on the time of physicians. "As the number of reps went up, the amount of time an average rep spent with doctors went down—so far down, that tactical scaling has spawned a strategic crisis. Physicians no longer spend much time with sales reps, nor do they see this as a serious problem." Marketers must decide on the appropriate size of a sales force needed to sell a particular portfolio of drugs to the target market. Factors influencing this decision are the optimal reach (how many physicians to see) and frequency (how often to see them) for each individual physician, how many patients with that disease state, how many sales representatives to devote to office and group practice and how many to devote to hospital accounts if needed. To aid this decision, customers are broken down into different classes according to their prescription behavior, patient population, their business potential, and event their personality traits. Marketers attempt to identify the set of physicians most likely to prescribe a given drug. Historically, this was done by drug reps 'on the ground' using zip code sales and engaging in recon to figure out who the high prescribers were in a particular sales territory. However, in the mid-1990s the industry, through 3rd party prescribing data (e.g., Quintiles/IMS) switched to "script-tracking" technologies, measuring the number of total prescriptions (TRx) and new prescriptions (NRx) per week that each physician writes. This information is collected by commercial vendors. The physicians are then "deciled" into ten groups based on their writing patterns. Higher deciles are more aggressively targeted. Some pharmaceutical companies use additional information such as: Profitability of a prescription (script), Accessibility of the physician, Tendency