This paper is a comparative study of weak pronouns in German and Hebrew. Weak pronouns share properties of both Romance-like clitics (adjacency, clustering effects) and full pronouns (non-reduced, free-standing forms). Weak pronouns are analyzed as maximal projections prior to Spellout and as clitics, X0 elements, at LF. In the overt syntax, they move as XPs to their Case-checking position. They move beyond the Case position if that position is not close enough to their LF-host. At LF they move as X0s, i.e. they cliticize and incorporate to a V-related host. In Hebrew, the clitic host is the participle (Agr participle0) in complex tenses and the verb in AgrS0 or in C0 (inversion) in simplex tenses. In German, the pronouns' LF-host is unique: AgrS0 raised to C0. Weak pronouns can form clusters, which are derived by multiple adjunction of the pronouns. Weak pronouns are also subject to an adjacency constraint, as a consequence of the Head Movement Constraint, operative on LF Incorporation.