The literature is full of data about thiol-based monolayers; however, relatively little is known about thioether self-assembly. Thioethers are more resilient to oxidation than thiols and offer the potential for control over nanoscale assembly in two dimensions parallel to the surface. Therefore, robust assembly schemes derived from thioethers may offer a new class of self-assembled systems with new and useful properties. We have performed variable temperature scanning tunneling microscopy studies of thioether self-assembly on both Au(111) and Cu(111) surfaces. Our results indicate that thioethers are capable of assembling in a much more defect free manner than alkane thiols. We find that the packing structure of the monolayers is dependent on the alkyl tail length of the thioether. Importantly, thioethers assemble on both Cu and Au surfaces at temperatures below 150 K without disruption of the surface metal atoms. In the case of Au(111), the herringbone reconstruction remains intact at all coverages and actually directs assembly at intermediate surface coverages.