A collagen device is prepared by mixing collagen with purified water for a period of time sufficient to form a mixture. The pH of the mixture is adjusted to a pH level sufficient to substantially solubilize the collagen. A first predetermined amount of the mixture is placed into a container. The mixture is subject to a lyophilizing process and formed into a collagen device. The collagen device is also cross-linked. The collagen device has a plurality of pores wherein a majority of the pores have a diameter of less than 10µm. To use the collagen device as an implant to replace, reinforce or strengthen bodily tissue, or to act as an adhesion barrier, the collagen device is placed in contact with bodily tissue and that contact is maintained until the collagen device is substantially resorbed within the bodily tissue.