The only bad thing about Greta Gerwig’s increasing prominence as a writer/director is that it means we’re going to get less of one of our most exciting movie actors.

Gerwig hasn’t given up acting — I had tickets to a canceled New York production of “The Three Sisters” this year that was to star her and Oscar Isaac — but we used to see her in a few movies per year and there’s no way she can keep that up now that she’s in demand behind the scenes. Maybe the silver lining is that she’s using this self-quarantine period to write new projects — like a script she has hinted has something to do with tap dancing?

Gerwig made a big impression early on in several microbudget, semi-improvised movies with director Joe Swanberg, so she was lumped in with the unfortunately named “mumblecore” movement of movies where hipsters jammed in coffee shops and nothing much happened. Mumbling or not, she made a big leap from her splashy role in Swanberg’s “Hannah Takes the Stairs” to the similarly low-budget “Baghead.” She’s one of those performers who creates the illusion that everything she says has just occurred to her, and that seeming spontaneity is a huge asset in “Baghead,” a bizarre movie that needs a relatable performer like Gerwig to ground it.

Hollywood picked up on that quality of hers, and spotlighted it well opposite Ben Stiller in “Greenberg,” where she plays the Audrey Hepburn role of a free spirit who helps the main character learn Deep Truths about himself. But her best-friend character is so clearly the most compelling person in “No Strings Attached” that it throws off the movie’s balance, and although she shines in it, the remake of “Arthur” is useless.

A shortage of interesting parts for her may be why Gerwig has concentrated on writing and directing, first in collaboration with Noah Baumbach on “Frances Ha” and then on her own with “Lady Bird” and “Little Women,” both of which earned her Oscar nominations. In her directing projects, her persona comes through even though she’s not on screen. There’s a directness and a modern sensibility that makes the movies, which take place in very specific times and places, feel like they have something to do with today.

“I’m so sick of people saying love is all women are fit for,” Jo March cries in “Little Women.” “I’m so sick of it. And I’m so lonely!” Gerwig’s characters want things — big things — even if they’re not exactly sure what they are. And most of her characters are women, hanging out with friends who also are women.

Saoirse Ronan, who played Jo and Lady Bird, never seems more vital than in Gerwig’s films. Their sensibilities seem to match in the same way Robert De Niro’s and Martin Scorsese’s do. So let’s hope the two of them cook up more titles to add to this list of Gerwig’s best, both in front of and behind the camera.

Little Women (2019)

It didn’t seem like we needed another “Little Women,” which had been beautifully filmed several times. Turns out we did, and for so many reasons: the depiction of reckless, young love, the interest in what makes Marmee tick, the portrait of 19th-century female ambition and the thrilling scene in which Jo demands that a publisher pay her what she’s worth.

Frances Ha (2012)

There are a lot of modest comedies in which Gerwig plays an unconventional young woman just starting to make her way in the world. This one even has a companion piece, “Mistress America,” by the same director (Baumbach, Gerwig’s spouse, also worked with her on both). “Frances” is the best of them, highlighted by an exuberant sequence in which the title character dances around Lower Manhattan to David Bowie’s timeless “Modern Love.”

Lady Bird (2017)

From her first movie performances, Gerwig had the authority and originality of a star. That’s true of her directing debut, too. The autobiographical film about a theater-mad teenager who can’t wait to get out of Sacramento has one of the funniest, tenderest, angriest mother/daughter relationships ever put on screen (played by Laurie Metcalf and Ronan).

Baghead (2008)

The genre mashup plays like four actors were asked to appear in a romantic comedy, but halfway through filming, the directors turned it into a horror movie. The main reason we hang with the wild tonal shifts in “Baghead” is Gerwig’s droll, resourceful presence.

Maggie’s Plan (2015)

Gerwig is the fulcrum of two screwball farces that take place in the present but seem inspired by Jane Austen (the other is “Damsels in Distress”). Here, she’s supported by writer/director Rebecca Miller’s dizzy, warmhearted screenplay. Her scenes with Julianne Moore, as one of many characters for whom Maggie functions as a bossy amateur therapist, are especially delightful.

20th Century Women (2016)

Gerwig plays one of a posse of women who help a single mom (Annette Bening) raise her son in the confusing late 1970s. It’s not a showy role, but the outstanding movie includes another zesty dancing scene from Gerwig.

The House of the Devil (2009)

A throwback to ’70s cheapies, the low-budget creepfest gets a huge assist from a Gerwig specialty: Her intelligence and candor make all the wildness around her feel real. Her character helps a friend on a babysitting gig that comes with complications: It’s in a haunted house, there’s a total eclipse and, oh, there are no children.