This book discusses three types of causatives in Igbo. These are the analytical (syntactic), the morphological and lexical causatives. The analytical and morphological causatives constitute what have been referred to as the -me causatives’. This is simply due to the fact that the main VP of both types of causative is headed by the causative verbal element -me. The causative verbal element -me has a dual morphosyntactic status. In the analytical causative, -me behaves as an autonomous verb, while in the morphological one, it functions as an affix.

Facts from topicalization, clefting and resumptive pronoun strategies according to the book reveal that the Igbo analytical causative consists of two clauses: a main clause and a dependent one. The -me morphological causative’ is derived from its analytical counterpart via incorporation (head-movement) (Baker 1988). The derived verb in the morphological causative construction comprises the causative -me and an embedded intransitive verb; both count as a unit in overt syntax with a single thematic grid.

The lexical causatives in Igbo are either non-bi-positional or bi-positional in terms of their morphological structure. Whereas some bi-positional verbs alternate their transitivity, others are either transitive or intransitive.Finally, it is assumed in the book, that Igbo bi-positional causative verbs are derived from the lexicon through a morphological merger.