If a compound adjective can be misread, use a hyphen.

In a temporary compound that is used as an adjective before a noun, use a hyphen if the term can be misread or if the term expresses a single thought (i.e., all words together modify the noun). (Example: “the adolescents resided in two parent homes” means that two homes served as residences, whereas if the adolescents resided in “two-parent homes,” they each would live in a household headed by two parents.)

Most compound adjective rules are applicable only when the compound adjective precedes the term it modifies. If a compound adjective follows the term, do not use a hyphen, because relationships are sufficiently clear without one. (Example: client-centered counseling but the counseling was client centered).

Write most words formed with prefixes and suffixes as one word. (Example: aftereffect and agoraphobia).

When two or more compound modifiers have a common base, this base is sometimes omitted in all except the last modifier, but the hyphens are retained. (Example: Long- and short-term memory)