An operator, not necessarily linear, will be called a Carleman operator if
the image of the positive elements in the unit ball are bounded in the univ
ersal completion of the range space. For certain Banach lattices, a class o
f (not necessarily linear) Carleman operators is characterized in terms of
an integral representation and in a more general setting as operators satis
fying a pointwise finiteness condition. These operators though not linear a
re orthogonally additive and monotone.