Therefore, the most important future challenge concerning firms as well as advertising agencies is certainly a "better understanding of the benefits of corporate socio-ecological responsibility in communications". Especially advertising agencies often lack the technical expertise to ensure that the communications of new sustainable messages are credible and fail to ensure that there is alignment between a client's corporate practices and external communications. This often leads to passed up marketing opportunities and hinders the creation of positive brand value. To overcome those barriers advertising agencies must gain expertise and experience in the fields of sustainable advertising, so the promotion of sustainability issues becomes part of a real corporate philosophy advertised through all communication channels.