This paper is concerned with the syntax and semantics of comparison phrases, as in: Compared to John, Bill is tall. Beck et al. (2004) claim that comparison phrases are non-compositional. This paper argues against that claim by first providing syntactic evidence that comparison phrases start out in an argument position of the scalar adjective phrase and achieve their adjunct position via movement. The author then gives a compositional semantics of comparison phrases that is based on degrees (or intervals) and treats them analogously to English clausal comparatives. He also discusses whether degree-based semantics are appropriate for expressions of comparison in natural language other than clausal comparatives (such as comparison phrases, for a NP constructions and phrasal comparatives).