智能障礙或發展遲緩者常伴隨有不良的適應行為問題，這些問題行為的背後其實是具有某種複雜的溝通意義和功能，只是一般人不清楚而已，行為分析學者建議可透過功能性評量來瞭解其行為表現的潛在動機。本研究係針對三位在教養機構接受教育之智能障礙學生，透過訪談教師、請教師填寫問題行為動機量表以及進行A-B-C行為觀察等三種功能性評量方式，來瞭解個案問題行為的可能動機，然後透過功能性分析進行假設考驗以及瞭解介阨策略對於問題行為處理的成效。 研究結果指出，不同的功能性評量方法所找出之可能行為動機，在三位受試者裡，除一位受試者較不一致外，其他兩位均相當一致。此外，根據行為動機所進行之介入處理，亦能適度地減少三位受試者的問題行為。

　　　　　Persons with mental retardation often display maladaptive behaviors. These behaviors seriously affect their daily living, study and social relationship with other people. However, these behaviors do not seem to be haphazard and without purpose. Instead, they may have complex communicative social functions. Recently many researchers suggest that teachers of mental retardation need to identify the purposes and functions of the maladaptive behaviors prior to provide intervention. As soon as the purposes of behaviors are identified, the retarded can be taught more appropriate communicative behaviors. The purposes of this study were to identify the behavior motivation of three students with mental retardation through teacher interview, rating scale and A-B-C observation. Based on the findings of these three methods, functional analysis was conducted to verify the hypotheses and to identify the effects of behavioral interventions. The results indicated that methods of functional assessment could identify similar behavior motivation in two of three subjects and the effectiveness of intervention for each subject could also be found.