Recent findings in non-engineering fields related to human factors are reviewed with emphasis on communication difficulties. Foundation engineering tasks are discussed in the context of their potential for problems related to human factors. In particular, case histories are used to demonstrate the significant influence of subformal communication and on-site decisions. The paper concludes with a discussion of alternative measures to reduce the negative effects of human factors. It is expected that increased awareness of this biases and limitations will stimulate efforts to reduce their effect.