We present the results of a series of radio , optical , X-ray and \gamma -ray observations of the BL Lac object S50716+714 carried out between April 2007 and January 2011 .
The multi-frequency observations were obtained using several ground and space based facilities .
The intense optical monitoring of the source reveals faster repetitive variations superimposed on a long-term variability trend at a time scale of \sim 350 days .
Episodes of fast variability recur on time scales of \sim 60 – 70 days .
The intense and simultaneous activity at optical and \gamma -ray frequencies favors the SSC mechanism for the production of the high-energy emission .
Two major low-peaking radio flares were observed during this high optical/ \gamma -ray activity period .
The radio flares are characterized by a rising and a decaying stage and are in agreement with the formation of a shock and its evolution .
We found that the evolution of the radio flares requires a geometrical variation in addition to intrinsic variations of the source .
Different estimates yield a robust and self-consistent lower limits of \delta \geq 20 and equipartition magnetic field B _ { eq } \geq 0.36 G. Causality arguments constrain the size of emission region \theta \leq 0.004 mas .
We found a significant correlation between flux variations at radio frequencies with those at optical and \gamma -rays .
The optical/GeV flux variations lead the radio variability by \sim 65 days .
The longer time delays between low-peaking radio outbursts and optical flares imply that optical flares are the precursors of radio ones .
An orphan X-ray flare challenges the simple , one-zone emission models , rendering them too simple .
Here we also describe the spectral energy distribution modeling of the source from simultaneous data taken through different activity periods .