Abstract: A book or other document clasping and page marking device (20) is formed as a generally U-shaped clip for passing around and clamping the edges of a set of pages and/or the cover of a book (10). The device consists of a generally U-shaped member of resilient material such as transparent molded plastic material having opposing arms (21, 24) which are normally flat in cross section and flat or curved in longitudinal section. One or both of the inside parts of the opposing arms, away from their junction, has a page-gripping surface which is serrated, grooved, roughened or otherwise treated or coated to lightly but firmly grip the device against a page when the device is clipped on a book, facilitating insertion of a page. The device (20) can be inserted into a selected position of a book edge wherein the joining part of the U and the adjacent parts of the arms of the device can protrude by a desired amount to provide a counter-balancing effect.