Although the particle ne has been studied by many linguists, including Chao (1968) and Li & Thompson (1981), only part of its contextual uses has been examined and hasty conclusions drawn. In this paper, data have been collected from Mandarin instructors, visiting scholars from China, novels and other texts published in either Taiwan or Mainland. Thus a wide range of contextual uses of ne has been collected, analysed, and the general/invariant meaning of this form has been extracted. The general/invariant meaning is then put in opposition to that of the zero sign (Ø) in order to determine the relational invariant meaning of this particle. My conclusion is that ne carries the relational invariant meaning [+ constrastiveness] while the zero sign is neutral so far as this semantic feature is concerned.