The travel industry is located at the midstream of the tourism and plays a crucial role in the integration of resources. However, due to its susceptibility to the season, business prosperity, and natural or man-made disasters, the market demand in travel industry is fairly instable. Moreover, the entry-barrier is rather low in this industry, which makes it so competitive that no single enterprise can predominate over others. Consequently, to form a strategic alliance has become an imperative to survive, and a PAK alliance has been proved to be effective in practice for many years. Many travel agencies in Taiwan have taken advantage of a PAK alliance to achieve goals like a high corporate achievement or product-line expansion¡Ketc. This research discusses chiefly about what attitude the scale of business have when joining in a PAK alliance, including their motives, partner-selection, and performance improvement. Furthermore, this study probes into key factors of the success of a PAK alliance and looks into the prospect of tourism. The major findings of this research are listed below: 1. Large-scale businesses participate in a PAK alliance mainly in view of the ¡¥¡¦motive of resources¡¦¡¦, and put much more emphasis on the ¡¥¡¦market strength¡¦¡¦ of their partners. However, an alliance offers nearly no help on the part of ¡¥¡¦financial performances¡¦¡¦. 2. Middle-scale businesses participate in a PAK alliance also mainly in view of the ¡¥¡¦motive of resources¡¦¡¦, and put much more emphasis on the ¡¥¡¦ consistency of business culture¡¦¡¦ between they and their partners. Besides, an alliance can substantially assist them in gaining ¡¥¡¦market strength¡¦¡¦. 3. Small-scale businesses participate in a PAK alliance mainly in view of the ¡¥¡¦motive of economy¡¦¡¦, and put much more emphasis on the ¡¥¡¦ consistency of business culture¡¦¡¦ and ¡¥¡¦network¡¦¡¦ between they and their partners. Besides, an alliance can substantially assist them in the ¡¥¡¦accumulation of organization competence¡¦¡¦. 4. Small-scale businesses pay much attention to the influence of ¡¥¡¦human factors¡¦¡¦ on the success of a PAK alliance. 5. All types of businesses consider it plausible and inevitable for alliance members to cause damage to the overall benefit, and when it does happen, they deal passively with it. 6. In the future, businesses would place little importance on PAK alliance; instead, they are supposed to think highly of the potentiality of their main products if they are competent and the market allows them to do so, and PAK products merely serve to increase the diversity of products.