The two-volume set LNCS 4668 and LNCS 4669 includes the peer-reviewed proceedings of the 17th International Conference on Artificial Neural Networks (ICANN 2007), which took place in September 2007 in Porto, Portugal. These volumes contain 197 revised full texts that have been carefully selected from 376 submitted papers. The first volume includes 98 contributions, organized into thematic sections addressing various aspects of neural networks, including learning methods, neural network architectures, and complex systems. These conference proceedings provide valuable insights into the latest developments and research in the field of artificial neural networks and are a significant resource for professionals and students in computer science.