I don’t spend a lot of time thinking about punctuation, but when I’m proofreading I consider every punctuation mark. Today I’m thinking about hyphens used with compound modifiers – and how following strict hyphenation rules can easily distract the reader.

Actually, there are few hard-and-fast rules about hyphenating compound modifiers. As a general rule, hyphenate a compound modifier that comes before a noun (full-time employees). But even then, you can use your own judgment.

 (Almost) always hyphenate

Hyphenate these compound modifiers when they come before a noun:

• Color terms when the elements are of equal importance (blue-green dress)
• A cardinal number and a unit of measurement before a noun (100-yard dash)
• Adjectival compounds beginning with high and low (high-level programming language)
• Adverb-adjective combinations (much-loved character)
• “Two-thought” compounds (socio-economic)

Hyphenate compounds beginning with self or half, whether or not they precede a noun:
I believed he was self-reliant. This idea turned out to be half-baked!

(Almost) never hyphenate

• Combinations that are ordinarily hyphenated before a noun are often not hyphenated
  after a noun: Employees who expressed satisfaction generally work full time.
• Don’t hyphenate adverbs ending in ly + a participle or adjective (a highly complex system).
• Word-forming prefixes do not require hyphens: anteroom, binomial, infrastructure.
• Proper nouns (anti-Semitic)
• Words that without hyphens could look like other words (un-ionized)
• Words with identical letters that need separating (pre-empt)

Exceptions to the almost-never-hyphenate rule:

Breaking the rules

All these rules are helpful, but style guides almost always admonish readers to seek clarity before slavishly following rules. Applied without restraint, hyphenation rules can result in a sea of hyphens that make the text difficult to read. If sentences are succinct and clear, I suggest not over worrying about hyphenation.