  We present experimentally derived potential curves and spin-orbit interaction
functions for the strongly perturbed $A^{1}\Sigma_{u}^{+}$ and $b^{3}\Pi_{u}$
states of the cesium dimer. The results are based on data from several sources.
Laser-induced fluorescence Fourier transform spectroscopy (LIF FTS) was used
some time ago in the Laboratoire Aim\'{e} Cotton primarily to study the $X
^{1}\Sigma_{g}^{+}$ state. More recent work at Tsinghua University provides
information from moderate resolution spectroscopy on the lowest levels of the
$b^{3}\Pi_{0u}^{\pm}$ states as well as additional high resolution data. From
Innsbruck University, we have precision data obtained with cold Cs$_{2}$
molecules. Recent data from Temple University was obtained using the
optical-optical double resonance polarization spectroscopy technique, and
finally, a group at the University of Latvia has added additional LIF FTS data.
In the Hamiltonian matrix, we have used analytic potentials (the Expanded Morse
Oscillator form) with both finite-difference (FD) coupled-channels and discrete
variable representation (DVR) calculations of the term values. Fitted diagonal
and off-diagonal spin-orbit functions are obtained and compared with {\it ab
initio} results from Temple and Moscow State universities.
