There are lots of Wash­ing­ton power lists out there already, but this one is dif­fer­ent. You’ll find no mem­bers of Con­gress here. This is about those work­ing be­hind the scenes, mem­bers of a group that’s over­worked but un­der-re­cog­nized: the most power­ful wo­men staffers on Cap­it­ol Hill.

This spring, Na­tion­al Journ­al con­tac­ted more than 1,500 con­gres­sion­al staffers in both parties and cham­bers—the people who’d know best—and asked them to nom­in­ate their col­leagues for this list. We promp­ted them to tell us about the most ex­cep­tion­al and ef­fect­ive wo­men they know: those who work tire­lessly for their bosses and causes, who take ac­tion and take chances, who dis­play lead­er­ship, and who gen­er­ally get things done.

We re­ceived nearly 200 nom­in­a­tions (which made nar­row­ing the list down to 20 no easy task). Our re­port­ers sat down with the fi­nal co­hort—be­low in no par­tic­u­lar or­der—to learn how they got here, what they’ve done, and why Con­gress would move even slower without them.

Read in­di­vidu­al pro­files of the most power­ful wo­men staffers on Cap­it­ol Hill: Di­ane Dewhirst | Jo Mar­ie St. Mar­tin | Char­lotte Iv­ancic | Janice Mays | Al­exa Mar­rero | Bar­rett Karr | Maura Keefe | Shan­non McGahn | Sarah Bolton | Tri­cia Rus­sell | Kat Skiles | Shar­on Soder­strom | Lyn­nel Ruck­ert | Jen­nifer DeCasper | Kate Le­one | Kristine Lu­cius | Brenda Jones | Maria Mei­er | Alex­is Covey-Brandt | Mo­nique Wa­ters

Read more from our Wo­men in Wash­ing­ton series: What’s It Like to Be a Wo­man on Cap­it­ol Hill? | Why Some Male Mem­bers of Con­gress Won’t Be Alone with Fe­male Staffers | What Young Fem­in­ists Think of Hil­lary Clin­ton |Wo­men’s Magazines Go Wash­ing­ton