  Previous approaches to the photo- and electro-production of strangeness off
the proton, based upon effective hadronic Lagrangians, are extended here to
incorporate the so called off-shell effects inherent to the fermions with spin
>= 3/2. A formalism for intermediate-state, spin 3/2, nucleonic and hyperonic
resonances is presented and applied to the processes $\gamma + p ---> K^{+} +
\Lambda$, for $E_{\gamma}^{lab}$ <= 2.5 GeV, $e + p ---> e' + K^+ + \Lambda$,
as well as the branching ratio for the crossed channel reaction $K^- + p --->
\gamma + \Lambda$, with stopped kaons. The sensitivity, from moderate to
significant, of various observables to such effects are discussed.
