This paper investigates the attitudes of clients towards unethical behavior in construction projects in the Gaza Strip. A questionnaire survey was adapted in this study. A total number of 220 questionnaires were distributed to construction projects clients and 162 questionnaires were returned, a 73.6% response rate. The results indicated that most respondents agreed there is a positive relationship between ethical behavior and long-term profitability of construction organizations. The majority of respondents believed improving ethical practice for professionals could improve ethical performance in construction projects, while unethical behavior may decrease quality. Respondents indicated the major difficulty in developing a strong ethical awareness is that unethical behavior is the prevailing trend within the industry. Most organizations have an ethical code of conduct, but there is great difficulty in applying it due to political and economic conditions. Respondents agreed that the most serious phase in the construction project life cycle affected by unethical behavior is the construction phase, followed by the bid evaluation phase.