It is a truth universally acknowledged that a partner in possession of a good book of business is in need of a better firm. If you are a partner considering such a lateral move, then you are probably focused on the boost a new firm could offer your practice and on cultural fit. These are certainly important factors in making a successful move. However, our review of the 2,353 partners who moved between Am Law 100 firms in 2010 through 2012 suggests some more prosaic factors matter too.

When should you make the move? Well, fall seems to be the time of year to start exploring seriously so that you can move early in the new year. As the columns in Fig. 1 show, the volume of lateral partner moves declines through the year from 35 percent of a year’s moves happening in the first quarter to 15 percent in the fourth quarter.