We present new theoretical models for surface brightness fluctuations in the near-infrared .
We show the time evolution of near-infrared brightness fluctuation properties over large age and metallicity ranges , i.e. , from 12 Myr to 16 Gyr , and from { Z / Z _ { \odot } = 1 / 50 } to { Z / Z _ { \odot } = 2.5 } , for single age , single metallicity stellar populations .
All the stellar models are followed from the zero age main sequence to the central carbon ignition for massive stars , or to the end of the thermally pulsing regime of the asymptotic giant branch phase for low and intermediate mass stars .

The new models are compared with observed near-infrared fluctuation absolute magnitudes and colours for a sample of Magellanic Cloud star clusters and Fornax Cluster galaxies .
For star clusters younger than { \sim 3 Gyr } , the predicted near-infrared fluctuation properties are in a satisfactory agreement with observed ones over a wide range of stellar population metallicities .
However , for older star clusters , the agreement between the observed and predicted near-IR brightness fluctuations depends on how the surface brightness absolute magnitudes are estimated .
The computed set of models are not able to match the observed near-IR fluctuation absolute magnitudes and colours simultaneously .
We argue that the observed discrepancies between the predicted and observed properties of old MC superclusters are more likely due to observational reasons .