And it will embody for many a new commitment to collaboration among its numerous institutions.

But the five-day gathering, which begins Sunday, also comes amid concern that the 100-year-old movement is too factionalized and may be losing clout.

Approximately 1,500 people are expected to attend the convention.

Among the firsts:

*Five Conservative groups that previously met independently — the congregational arm, rabbinic arm, and three professional associations for synagogue executive directors, educators and cantors — will share one conference.

*A woman, Judy Yudof, will head the movement's congregational arm, the United Synagogue of Conservative Judaism.

Neither the Orthodox nor Reform body has had women serve in a comparable role, but the smaller Reconstructionist movement has.

*An Israeli rabbi will head the movement's rabbinic arm, the Rabbinical Assembly.

Rabbi Reuven Hammer, who made aliyah from the United States in 1973, was one of the rabbis involved in the Ne'eman Commission, a group that sought in the late 1990s to find a compromise among the religious streams over contentious issues related to conversion.

*An Ethiopian-born Conservative rabbi, Yafet Alemu, who was ordained in Jerusalem in November, will be inducted into the Rabbinical Assembly.

More traditional than Reform, more liberal than Orthodox, the Conservative movement views halachah, or Jewish law, as binding but takes a more liberal interpretation than Orthodoxy.

While most of its leaders observe Shabbat and keep kosher, the majority of its rank-and-file synagogue members — unlike Orthodox synagogue members — are not strictly observant.

While the Reform movement has reached out to intermarried families and to gay and lesbian Jews, the Conservative movement — while welcoming intermarried Jews — does not allow non-Jewish spouses to become synagogue members. It also does not ordain openly gay rabbis.

Conservative leaders say they are facing numerous challenges, including trying to unite the movement and inspire members to take their Judaism more seriously at a time when the movement is not growing and in fact may be shrinking.

Both the Reform and Conservative movements say approximately 320,000 households in North America are affiliated with their synagogues. However, the Conservative movement used to be larger than Reform.

In the 1990 National Jewish Population Survey, 18 percent of American Jews were affiliated with Conservative synagogues and 16 percent with Reform ones, said Steven Cohen, a sociologist at the Hebrew University of Jerusalem who was involved with the study. In previous studies, the Conservative movement had been even larger, Cohen said.

Some in the Conservative movement say that Reform's recent growth may be because it is more unified.

While Reform's many institutions are united under the rubric of the Union of American Hebrew Congregations — which hosted its biennial gathering in December with 5,800 people — the Conservative movement is decentralized. Its many institutions not only raise funds separately but have reputations for not communicating among themselves.

"There are an awful lot of people who view this as the Conservative coalition, not a movement, at best a confederation," said Rabbi Daniel Allen, president of the Masorti Foundation for Conservative Judaism in Israel.

Next week's gathering — which brings together five institutions for the first time — is an effort to start to unite the movement, say Conservative movement leaders.

The Reform movement's more united structure "would be something I'd like to emulate," said Yudof, the United Synagogue's incoming president.

She said she has spoken recently with the heads of the Rabbinical Assembly and the Jewish Theological Seminary to discuss how the groups can work more closely, adding that all acknowledged the need for change.

"Neither debated the fact that the arms are speaking at each other rather than with each other and they seemed interested in how we might be able to work more collaboratively," said Yudof, who is from Minneapolis.

JTS is not part of the convention, but its chancellor, Rabbi Ismar Schorsch, and some of its leadership will attend.

In addition to the Balkanization of the movement's national institutions, Yudof said individual members are disconnected from the larger movement.

"There's a tendency to withdraw into the political life of one's own community and not have global view of the movement," she said.

Some in the field say it is getting more difficult to recruit members to their synagogues.

Elisa Spungen Bildner, who calls herself a "very committed" Conservative Jew and is a co-founder of the Foundation for Jewish Camping, said the "competition is fierce" for potential synagogue members.

"It's much easier not to be a Conservative Jew," Bildner said. "Coupled with so many intermarriages and the acceptance of the intermarried by the Reform movement, it makes the Conservative movement's job tough."

Bildner, who belongs to Congregation Shomrei Emunah in Montclair, N.J., said she recently spoke for two hours with the synagogue's membership chair about the challenges. "I look at Conservative Judaism as a way to be egalitarian and also observant, which Orthodoxy does not allow me to do. That's what propels me." But around her, she sees "declining numbers of religiously observant or committed Jews."

Conservative synagogues, she said, require more knowledge of Hebrew and liturgy than Reform ones, although in recent years, Reform synagogues have incorporated more Hebrew and more traditional rituals.

"I've watched people leave because one member of a couple doesn't have that level, and go to where there's less Hebrew, i.e., to Reform," Bildner said.

However, others are more optimistic. Riv-Ellen Prell, an American studies professor at University of Minnesota who has studied the Conservative movement, said one can see the "vitality of the Conservative movement in the growth of day schools and in the ongoing and growing popularity of the Ramah movement, whose camps are oversubscribed."

One of Yudof's goals is to inspire more Conservative Jews to become knowledgeable and observant. "When someone says they don't keep kosher or are not shomer Shabbos," or Sabbath observant, "we say to them politely, 'Not yet,'" she