More numbers, Bobert...

"Estimates of the number of Arabs who fled the newly-created State of Israel in 1948 (i.e. from the area inside Israel's pre-1967 borders) vary from 430,000 to 957,000, depending on who you ask. The most reliable figure appears to be 539,000.
In the 1967 Six Day War, between 125,000 (Israeli estimate) and 250,000 (UNRWA estimate) Arabs fled from Judea, Samaria and Gaza, which came under Israeli administration. Of these, say some researchers, close on two-thirds were first-time refugees, the others were refugees from 1948 who fled once again.

According to the United Nations Relief Works Agency (UNRWA), in 1996 the number of refugees stood at 3.3 million, located as follows:

Jordan: In 10 camps - 242,922. Not in camps - 1.1 million

Judea and Samaria: In 20 camps - 147,302. Not in camps - 385,136

Gaza: In five camps - 378,279. Not in camps - 338,651

Lebanon: In 12 camps - 182,731. Not in camps - 169,937

Syria: In 10 camps - 89,472. Not in camps - 257, 919

TOTAL: In 57 camps - 1.04 million. Not in camps - 2.26 million.

- Middle East Digest - October 1998

The refugee problem was created in 1947-48, when the Palestinians and their Arab allies rejected United Nations Resolution 181 and tried to prevent by force implementation of the partition plan that called for the creation of a Jewish state alongside an Arab state in Palestine. During the fighting, 600,000 to 700,000 Arabs fled or were driven out of areas that eventually became the state of Israel. (There were also about 17,000 Jewish refugees who fled or were driven out of areas that came under Arab, i.e., Jordanian, control.) Israel's record in this chain of developments was far from spotless. But the major reason for the displacement of people was the war itself, which the Arabs imposed on Israel in an attempt to abort its birth.
The Palestinian refugees were but one example among many of the large-scale involuntary population displacements that took place during and after the First World War. Most of the other refugee problems, involving tens of millions of Karelian Finns, Sudeten Germans, and Muslims and Hindus in the Indian subcontinent, faded away as displaced populations were absorbed in countries of similar religious and/or national character. The one glaring exception was the Palestinian refugees, who found shelter but few civic or political rights in neighbouring Arab countries (Jordan being the main exception).

The refugee status of the Palestinians was perpetuated by the host countries and the Palestinian leadership, and by the international community, through the UN Relief and Works Agency (UNRWA), the only UN body dedicated to a specific refugee group (all other refugees in the world are the responsibility of the Office of the UN High Commissioner for Refugees). As a result, refugee status was passed down from father to son to grandson over 50 years, so that, today, they number three million to four million. That is why the Palestinians now account for about one-fourth of the world's refugees -- an impressive figure until one imagines how many refugees there would be if all the Finns and Germans and Indian Hindus and Muslims and European Jews who were made refugees after the Second World War (not to speak of the Greeks and Turks and Armenians who were made refugees during and after the First World War) were still considered refugees in the year 2000.

- Mark Heller, co-author of No Trumpets, No Drums: A Two-State Settlement of the Israeli-Palestinian Conflict

With regard to the Palestinian refugees today, according to the "Report of the Commissioner-General of the United Nations Relief and Works Agency for Palestine Refugees in the Near East - 1 July 1997 - 30 June 1998" there were 3,521,130 refugees as of June 30, 1998 (Table 1). However, the report (available at www.unrwa.org) also states that:
UNRWA registration figures are based on information voluntarily supplied by refugees primarily for the purpose of obtaining access to Agency services, and hence cannot be considered statistically valid demographic data; the number of registered refugees present in the Agency's area of operations is almost certainly less that the population recorded.
Moreover, not only does the UN admit the figures are of doubtful accuracy, there being obvious reason for families to claim more members and thereby receive more aid, the UN also admits that the total includes 1,463,064 Jordanian citizens, who cannot by any stretch be considered refugees.
- Alexander Safian, PhD, CAMERA (The Committee for Accuracy in Middle East Reporting in America)