音樂產業嘗試藉由降低價格與增強著作權執法來抑制盜版風氣的蔓延，卻未能收到預期成效。本文由盜版行為具有社會文化特質的角度出發，設計一個很簡單的社會風俗模型，來呈現盜版風氣可能如何逐漸普及，而演變成一種穩定的流行文化或社會風俗。並說明當盜版已成為一種穩定的社會風氣後，音樂商品價格調降與法制提升，可能都無法消弭甚至很難減輕盜版風氣。由於盜版盛行可能對正版廠商的利潤造成難以回復的嚴重傷害，此特性會使廠商調高價格的行為趨於保守。 Conventional economic reasoning predicts that the music industry's effort in curbing piracy through reducing price and strengthening enforcement will be effective. Recent industry trends in terms of sales and profit say otherwise. This paper models piracy as an individual's consumption decision shaped not only by economic variables such as price but also by social norms à la Akerlof (1980) to account for the music industry's failure. It is shown that, when piracy has developed as a social norm, price and enforcement adjustments may be rendered ineffective. A prevailing piracy norm also results in severe damage to the firm's profit and the firm will drastically change its price-setting behavior.