在今日的經營環境中，客戶的需求有賴多個企業共同來滿足。合作與競爭關係往往同時存在於兩個公司之間，使得僅針對競爭或僅探討合作關係的傳統策略分析方法，產生了侷限。因此，以「一群相互連結，共同創造價值與分享價值的企業」為研究對象的「商業生態系統」觀點，逐漸受到重視。但過去相關研究主要著眼於商業生態系統中廠商的角色，對於商業生態系統整體的變遷較少著墨。 本研究採用歷史分析方法，以軟體產業為研究情境，探討商業生態系統的變遷。研究主要描述軟體在1950年代末期由硬體獨立出來後形成之商業生態系統以及其變遷的過程。本研究主要發現，隨時間經過，軟體業由高度垂直整合，逐漸走向水平分工，在產業逐步出現「零碎」的現象的同時，大小不一的次系統中「關鍵者」與「利基者」快速更迭交替。 本研究主要貢獻在於透過歷史分析法清楚描繪並歸納出變化迅速的軟體業之變遷動態。有別於以往靜態的分析模式，研究結果具有理論與實務的參考價值。對於「商業生態系統」理論而言，本研究藉由商業生態系統變遷過程之探討，發現廠商角色之迅速更迭交替，並建議研究者未來可進行更多動態的研究。在實務上，對於廠商而言最重要的意涵在於，不論是否具有主導地位，廠商都應了解並掌握整體商業生態系統的變遷，才能在瞬息萬變的經營環境中長久生存。

In today's business environment, firms can no longer fulfill all customers' needs alone. They need to work together to meet customers' requirements jointly. Many firms therefore, inevitably, share a common fate. However, firms now very often cooperate, while at the same time compete with each other. Under such a circumstance, traditional strategic analysis frameworks appear to have their limitations. A new approach, business ecosystem perspective, has thus gained popularity. This new approach, by analyzing a group of interconnected firms who jointly create and share value, has been providing significant insights for both academia and practitioners. However, past business ecosystem researches have focused more on the inter-firm relationships, leaving the development process of business ecosystems untouched. Our study endeavors to fill the gap. Using software as research context, we adopt historical analysis as our methodology to explore the development process of business ecosystems. We describe, in the current study, the process of how software was separated from hardware in the late 1950s to form a business ecosystem, and how the software business ecosystem developed and morphed later. Our research findings reveal that, as the software business ecosystem developed, many "sub-systems" were formed. Each sub-system has its own "keystones", firms with dominant power in the sub-system, and "niche players", firms without dominant power in the same sub-system. In addition, different keystones are found during different period of time. Furthermore, not only keystones, but also niche players in a business ecosystem constantly change their roles. Therefore, firms are advised to fully understand how business ecosystems are developed and catch the trend of change, so they can survive in the long run.