The rate of adsorption of polystyrene from cyclohexane solu tion on chrome felTo ty pe plates ",as studi ed for a concentration range of 10-1 to 10-4 mg!m l. 1'\\' 0 molec ular weight fraction s of p oly mers, 76,000 and 38, 100, were prepared by t h e anionic poly m erization of sty re ne tagged with t ritium , and a radiotracer technique was used t o m easure directly the a moun t of polyme r adsorb ed on t h e surface. The rate of adsorption is very d ep endent on t he cOllecntration of t h e poly mer solution, a nd t imes vary ing from minutes to sever al hours wcre r equ ired before maximum adsorption occurred for th e concen t ration ra nge studied. Th e ra te of d esorption is strongly dependent on t he adsorbance; it was hypo t hes ized that t his is d ue to t he number of attachme nts per molec ule also va ry in g with adsorbance. The conformatio n of the adso rbrd molecule as indicated by these res ults a nd those determined by t he measurement of th e thickncss of the adso rbed laycr by ellipsometr y is disc ussed.