Many structures (buildings, bridges,....) are supported on deep foundations such as driven piles. In some types of structures the piles are driven at small horizontal spacings and are subjected to horizontal loadings. Examples of such structures include offshore oil production platforms and bridges subjected to lateral loads from wind and ocean currents. No reliable design method exists for such cases and, as a result, the designs currently used are probably conservative in most cases, i.e., larger than necessary amounts of money are spent to ensure that failure does not occur. The level of uncertainty is such, however, that excessive movements sometimes occur and lead to distress in the structure that is supported on the piles. Recently, several series of full scale lateral load tests were performed using pile groups so that reliable information is now available to use as a check on the accuracy of analyses. This project involves the first attempt at a full-scale numerical analysis in three dimensions, of pile groups, using the socalled finite element technique. It should provide a level of insight not previously possible. It may provide a design tool for major foundations and data to be used in simplified analyses for less complex cases.