The optical properties of

{Nd}^{3 +}

ions in six different compositions of glasses based on

{GeO}_{2},

PbO, and

{Bi}_{2} O_{3}

have been investigated by using steady-state and time-resolved laser spectroscopy. Judd-Ofelt parameters were derived from the absorption spectra and used to calculate the

^{4} {\vec{F_{3 / 2}}}^{4} I_{11 / 2}

stimulated emission cross section and the

^{4} F_{3 / 2}

radiative lifetime. Site-selective spectroscopy and time resolved fluorescence line narrowing experiments were performed in the

^{4} {\vec{F_{3 / 2}}}^{4} I_{9 / 2},^{4} I_{11 / 2}

transitions. For all samples studied a line narrowing of the

^{4} {\vec{F_{3 / 2}}}^{4} I_{11 / 2}

emission has been observed when exciting at the long wave side of the

^{4} {\vec{I_{9 / 2}}}^{4} F_{3 / 2}

transition. The lifetimes of the

^{4} F_{3 / 2}

state do not show a monotonic variation with the excitation wavelength indicating large site-to-site variations in the local crystal field. Spectral migration of excitation among the

{Nd}^{3 +}

ions has been studied from the time evolution of the

^{4} {\vec{F_{3 / 2}}}^{4} I_{9 / 2}

spectra under resonant excitation. The results can be interpreted in terms of a dipole-dipole energy transfer mechanism. Visible upconversion has been observed in these glasses under infrared laser excitation.

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