Fig.: to be actively involved or informed of currents affairs or events. To be in the tick of things

Investment is a hazardous business; even those who are in the swim sometimes come a cropper

Il settore degli investimenti è sempre rischioso; anche i più informati a volte finiscono male

The Browns are retired and Mrs. Brown is always in the swim of charity funds raising, while her husband seems out of the swim in politics, his former occupation

I Brown sono in pensione e mentre la sig.ra Brown è sempre in piena attività nel giro degli eventi di beneficenza, suo marito sembra ormai fuori dal giro politico, la sua precedente occupazione

This term, dating from the mid-nineteenth century, comes from fishing. In fact, a large number of fish in one location was sometimes called "a swim." It later came to mean the main current of affairs