Museum on its Way Up. A dynamic Florida museum spotlights joyous art from Haiti, while Cinq Soleils, an artist's collective near Port-Au-Prince, works to reverse decades of exploitation and build an environment where art can flourish

THREE years ago, when Fort Lauderdale opened a new home for its Museum of Art, this city joined a growing number of smaller American cities with new museums designed by major architects. Fort Lauderdale chose the internationally acclaimed Edward Larrabee Barnes, who designed a starkly effective $7.5 million building with expansive, well-lighted galleries, a spacious outdoor sculpture terrace, carefully laid-out work areas, and a sweeping, dramatically positioned grand staircase. Of particular interest here (through May 28) is a fascinating and moving survey of Haitian art called ``Where Art Is Joy.'' For this temporary exhibition, curators Selden Rodman and Candice Russell have put together 127 paintings, sculptures, and various ``folk'' items produced in Haiti over the past 40 years.

I wish this show could travel to New York, for it would help dispel many of the notions that Haitian art is of low quality. Absent from the pieces assembled here are the slick, decorative, highly commercialized, and mass-produced depictions of Haitian life that have flooded the American market these past 30 years. Instead the curators have selected gentle, smallish pieces of uninhibited imagination and joyous spirituality, crude and naive by some standards, but delightful, touching, and impressive by others.

Also on view in the main gallery area (through May 28) is an eye-popping retrospective of 50 of Trevor Bell's large shaped-canvases and works on paper. It's a stunning show, even though it lacks the heart and spirit that permeate most of the Haitian pieces.

The museum itself has come a long way in a short time. Most visitors would be surprised to learn that it is only 31 years old, having been founded in 1958 by the local Junior League. Its first home was a remodeled store, its second a two-story building that was woefully inadequate by the end of the first year of occupancy, 1969.

Fortunately, space is no longer a problem. Any museum director would be delighted with the new Barnes building's large and subtly illuminated main exhibition galleries, which are suitable for huge paintings and sculptures and for more intimately scaled objects and works on paper.

Indeed, one suspects that Kenworth Moffett, the museum's just-appointed executive director, found this building's openness and flexibility irresistible when he accepted the position.

On the other hand, Mr. Moffett must also realize he is arriving at a critical point in the museum's development. As yet, there is no well-thought-through or well-funded acquisitions program. Its outstanding building and first-rate programs cannot quite hide the fact that its permanent collection is limited and largely unfocused. As yet, there is no well-thought-through or well-funded acquisitions program. And financing - always a serious problem for any museum, especially a private one with public commitments - is of particular concern here.

The museum, in short, is at a crossroads: It has a beautiful new building; a well-rounded exhibition policy; an outstanding education program; and a dedicated and thoroughly professional staff. What it lacks, however, is something only time and money can remedy: a permanent collection of consistent depth and substance.

It already has a good foundation to build on. Its collections of Oceanic, West African, Pre-Columbian, and American Indian art are superb. And there are enough good to excellent examples of work by Rembrandt, Renoir, Matisse, Picasso, and more recent painters and sculptors to make a visit here memorable. The museum also has one of the world's finest holdings of Cobra art (works produced between 1948 and 1951 by the Cobra group of Expressionist artists in Copenhagen, Brussels, and Amsterdam), but that movement was only a peripheral one, and its products, while often quite remarkable, don't draw widespread public and professional attention.

Assembling a first-rate collection of masterworks requires a significant number of patrons and of collectors who are willing to give their precious works to the museum. So far, Fort Lauderdale has been fortunate in the matter of gifts. And in the meantime, there are fine temporary exhibits like the Haitian show to round out the basic collection.