explore topics such as the Jewish tradition in the modern world, how Jewish life in Israel differs from Jewish life abroad, and how mandatory military service impacts young Israelis' perceptions of service and commitment to their country. More than 115,000 Israelis have participated in the program since 2000. Participants have the option to extend their plane ticket for up to three months to explore Israel and the region. The optional extension is not part of the Birthright trip, and the participant is in that time like any tourist. Security measures Security policies in place during the trip "ensure a comprehensive safety umbrella", as follows: No travel to the West Bank, Gaza, or East Jerusalem other than the Jewish Quarter of the Old City Participants in each group remain together at all times and follow a set schedule of activities Participants do not leave the groups to travel, explore or visit with Israelis on their own during the ten-day trip Public transportation is not allowed at any time At least one highly trained, armed escort accompanies each group throughout the entire trip Cost and Funding Each trip cost approximately $4,500 as of 2020. According to Birthright Israel, 67% of funding comes from individual donors, 27% from the Israeli government, 3% from Jewish federations, and 3% from the Jewish Agency. The largest individual donor is the Adelsons, who had given more than $250 million to Birthright Israel by 2015. Other major donors include prominent philanthropists Charles Bronfman, Edgar Bronfman, Sr., Daniel Och, Marlene Post, Lynn Schusterman, and Michael Steinhardt.The program also receives funding from the German government, through the Conference on Jewish Material Claims Against Germany. Alumni programs Between 2007 and 2015, Birthright NEXT was a program intended to act as a post-trip follow-up organization to keep youth involved in local Jewish communities after visiting Israel via Birthright. One NEXT initiative was I.D., in which Birthright Israel alumni would perform monologues based on their experiences. In early 2009 it split into a separate entity, but the two organizations shared most board members. Ultimately, a lack of funding for alumni programs in the face of an increased emphasis on youth Israel trips led NEXT to be shut down by 2015. Impact Impact on Jewish identity Leonard Saxe of Brandeis University's Cohen Center for Modern Jewish Studies has evaluated the program's impact since its inception in 1999. As of 2020, findings include: Birthright participants