In recent years, two demographic issues have captured headlines: whether and how demographic trends between Israelis, Palestinians and the neighboring countries affect the strategic balance; and whether demographic trends, perhaps a little differently, influence the existence of Jewish communities in the world and the nature of Israel-Diaspora relations, thereby again affecting Israel's strategic balance. Interestingly, the deeper the demographic processes have been investigated, and the better recent research reports have provided insights on the causes and consequences of population change, the more disagreements and polemics have emerged about the substantive thrust of Jewish demography. It has been maintained, for example, that serious mistakes have led to significant overestimates of the Palestinian population, so that the percentage of Jews in Israel and Palestine is significantly higher than previously thought. It has also been suggested that the number of US Jews has been significantly underestimated, so that the position of the Jewish Diaspora is far more rosy than usually believed. These discussions, besides normal and legitimate perceptional differences, often unveil a personal tone of denial of the other's opinion, or even of the other's professional integrity, if not loyalty, to Jewish or Israeli identity. WHY SUCH passion? Who is right and who is wrong? Is it possible at all to provide answers to questions concerning Jewish demography and identity? And is it important at all? At least part of the answers will come during the next few days from the international conference on the future of world Jewry convened by the Jewish People Policy Planning Institute, with the participation of president-elect Shimon Peres, Prime Minister Ehud Olmert, ministers, the heads of world Jewish organizations, as well as rabbis, intellectuals and researchers from Israel and the world. Central in the debates will be the assessment of trends in the Jewish family in Israel and in the Diaspora, new patterns of aliya and Jewish migration, the changing nature of Jewish identification, defining the boundaries of the Jewish collective and the rules for joining. The link between demography, identity and identification will be examined with the aim of developing an array of policy suggestions to be brought to the attention of decision-makers in Israel and across world Jewry. THE COMMON thread of all of these issues is a diffused sense that facing the growing challenges from outside and from inside, while world Jewry stagnates at zero population growth, there is a need for new ideas - here and now. As against the current trends, time is working against us. Quite a hot debate exists on whether the Jewish majority over the whole territory of the State of Israel and the West Bank - the area dominated by Israel since the disengagement from Gaza - is 62%, as maintained by the pessimists, or 67%, according to the optimists. But everyone would agree that the current rate of population increase is nearly double among the Palestinians in Israel and in the territories than among Israeli Jews. Over this whole territory in question, the percentage of Jews out of total inhabitants is declining year by year. This trend increasingly raises the question of the ability of the State of Israel to provide Jewish identity and civilizational experience to its citizens, without compromising democratic principles and of civil rights. The volume of Jewish immigration - currently close to its minimum historical levels - does not contribute much to the Israeli population balance. As against this, Jews in Israel still aim at an ideal family size of four children. This uniquely Israeli ideal goal will not be attained unless active steps are taken in the economic sphere concerning facilities for moving to larger housing, developing the existing early childhood infrastructure, and carefully monitoring the implications of motherhood for women's personal achievement - including women's working conditions and leaves of absence. AMONG DIASPORA Jewry, another stormy debate has developed over the real rate of out-marriage among American Jews - whether it is 45% or 55%. But few would question that based on the available evidence and under the present circumstances, out-marriage is a factor of erosion of the younger Jewish generation and thus contributes to the ongoing Jewish population aging and decline. Diaspora Jews are far from even approaching the level of generational replacement that still prevails in Israel. Judaism, quite obviously, does not begin or end with numbers. However, one should be careful about expecting the growth of quality while totally disregarding quantity. An adequate critical mass constitutes one among other significant existential prerequisites - in the realm of security in the tense environment of the Middle East, and in the cultural realm in the open and forthcoming environment of the Western countries which host the vast majority of world Jewry. The question of conversion of the non-Jewish members of out-married families has been pushed to the margins of the national agenda by an elite which coherently pursues lofty spiritual norms, but seems less attentive to the need to nurture the broader Jewish collective inclusive of all of its nuances, in the spirit of klal Yisrael. Population is the human capital upon which rests the future of Israeli society as a sovereign political entity and the ethnic core of worldwide Jewry. These days, globalization deeply delves into security, economy, communications, cultures and identities of world society in general, and of the Jewish collective in particular. UNDER THE dynamic conditions of the present and the foreseeable future, different environments challenge Jewish existence to the limits of the possible - through distinctly different provocations in Israel and in the Diaspora. In Israel, questions of physical security still bother and demand creative solutions, where the human demographic component occupies a central place. Elsewhere, the critical question is how to preserve the spark of Jewish collective pride among a youth increasingly exposed to the seductions of individual self-realization and personal freedom. At the intersection of the individual with the collective, and of the biology of birth and death with the cultural symbolism of continuity and creativity, the demographic predicament is going to be part of any future policy planning aimed at a better Jewish future. The writer, a senior fellow at the Jewish People Policy Planning Institute, holds the Shlomo Argov Chair on Israel-Diaspora Relations at the Hebrew University of Jerusalem.