本文檢驗2008~2012 年台灣上市公司董事會董事成員忙碌程度與公司風險承擔及債務資金成 本的關聯性。理論上，一家公司的董事若身兼多職，對於每一家公司所投入的監督努力、承諾以 及所提供的諮詢功能將相形下降，這將惡化了代理問題，公司經理階層有可能承擔過高的風險， 對於公司價值與企業風險有負面影響，反映在較高程度的風險承擔與較高的債務資金成本上，此 為忙碌假說；另一方面，一位身兼多職的董事有他的聲譽、有他經歷多家公司的專業、經驗與人 脈，這些皆有助於提升其對於管理階層的監督並發揮影響力，有助於減輕代理成本，對於降低公 司風險與提升公司價值皆有正面助益，反映在較低的風險承擔程度與較低的債務資金成本上，此 為聲譽假說。本文搜集各家上市公司董事會的各個董事在其他上市公司同時擔任董事的數目來衡 量董事會的忙碌程度，利用基本統計量及迴歸分析評估公司董事會董事成員忙碌程度與公司風險 承擔及債務資金成本的關聯性。雖然透過基本統計量的分析發現，董事會忙碌程度與公司風險承 擔程度並未有顯著的關聯性，但大部分的迴歸估計結果顯示，董事會的忙碌程度與公司債務資金 成本呈現負相關，較高的董事忙碌程度對應著較低的債務資金成本以及較佳的信用評等，因此， 本文的實證結果傾向支持聲譽假說。

This study examines the linkage among director’s multiple board appointments (busyness), degree of risk-taking and cost of debt of listed-companies on Taiwan Stock Exchange (TWSE) from 2008 to 2012. Theoretically, busyness hypothesis advocates that if a director with multiple board appointments, his/her efforts and commitment on managerial monitoring and professional advising toward each company is diluted. Therefore, agency problem is deteriorated due to higher risk-taking by the management, and the firm value is potentially worsened and risk of company lights up. On the other hand, reputation hypothesis postulates that busy director with greater reputation, professional skills, experience and interpersonal relationship has positive influences on company thereby reducing risk and enhance company’ s value. We hand-collect the number of directors of each listed company board that also serve as director in other listed companies and relates this degree of director’s busyness to the firm’s degree of risk-taking, cost of debt and credit ratings. Empirical finding shows that, although there is little evidence of significant correlation between degree of busyness and risk-taking, there is significant negative association between director’s busyness and cost of debt in terms of lower interest expense to total interest-bearing debt and favorable credit ratings. The principal outcome supports the view of reputation hypothesis such that busy board has capital markets benefit.