Hyphenation Headaches: Navigating -ly Adverb Rules

Many Right Touch Editing clients use the term cost-effective in their marketing collateral, including the variation cost effectively, as in: We are cost effectively providing. 

A client once asked: “Should cost effectively be hyphenated? Cost-effective is hyphenated in Merriam-Webster’s, but I keep bumping into the rule about not hyphenating –ly adverbs in my grammar and style books.”

Compound adjectives like cost-effective are hyphenated, but compound adverbs with –ly adverbs generally are not. H...