At its meeting in April 1990 at the University of Cambridge, the Executive Committee of the International Mathematical Union (IMU) decided that the largely unorganized archives of the Union should be properly arranged and catalogued. Simultaneously, the Executive Committee expressed the wish that a history of the Union should be written [1). As Secretary of the Union, I had proposed that these issues be dis cussed at the Cambridge meeting, but without having had in mind any personal role in the practical execution of such projects. At that time, the papers of the IMU were stored in Zurich, at the Eidgenossische Technische Hochschule, and I saw no reason why they could not remain there. At about this time, Professor K. Chandrasekharan produced a handwritten article titled "The Prehistory of the International Mathematical Union" [2), and it seemed to me that this might serve as the beginning of a more compre hensive history. I had first thought that Tuulikki MakeUiinen, who during eight years as the Office Secretary ofthe IMU had become well acquainted with the Union, would do the arranging of the archives in Zurich. She had a preliminary look at the material there, but it soon became clear that the amount of work required to bring order to it was too great to be accomplished in a few short visits from Helsinki. The total volume of material was formidable.

In recent years, mathematical logic has developed in many directions, the initial unity of its subject matter giving way to a myriad of seemingly unrelated areas. The articles collected here, which range from historical scholarship to recent research in geometric model theory, squarely address this development. These articles also connect to the diverse work of Väänänen, whose ecumenical approach to logic reflects the unity of the discipline.

The future of education centers empowered students in a global learning ecosystem. Despite decades of reform, the traditional borders of education—graduation, curriculum, classrooms, schools—have failed to deliver on the goals of excellence and equity. Despite massive societal changes, education remains controlled by an old mindset. It is time to change that limiting mindset and, more importantly, the ineffective practices in education. To truly serve all learners, future classrooms must remove the boundaries of learning and become student-centered, culturally responsive, and personalized—supportive and equitable environments where each student can direct their own learning and seek multiple pathways to skills and knowledge in a global learning ecosystem. This compelling call for transformative change offers all involved in education Evidence-based arguments that reveal the need to break the traditional borders that limit learning Strategies to personalize learning and remove the confinement of traditional pathways Examples from around the world to create equitable and student-centric learning environments Resources for creating a school learning environment that expands opportunities for personalized learning into the global learning ecosystem It is time to now imagine a different kind of learning, without borders, and to begin the shifts in practice that will result in personalized learning for all students.

In recent years, mathematical logic has developed in many directions, the initial unity of its subject matter giving way to a myriad of seemingly unrelated areas. The articles collected here, which range from historical scholarship to recent research in geometric model theory, squarely address this development. These articles also connect to the diverse work of Väänänen, whose ecumenical approach to logic reflects the unity of the discipline.

Rebellion, insurgency, civil war-conflict within a society is customarily treated as a matter of domestic politics and analysts generally focus their attention on local causes. Yet fighting between governments and opposition groups is rarely confined to the domestic arena. "Internal" wars often spill across national boundaries, rebel organizations frequently find sanctuaries in neighboring countries, and insurgencies give rise to disputes between states. In Rebels without Borders, which will appeal to students of international and civil war and those developing policies to contain the regional diffusion of conflict, Idean Salehyan examines transnational rebel organizations in civil conflicts, utilizing cross-national datasets as well as in-depth case studies. He shows how external Contra bases in Honduras and Costa Rica facilitated the Nicaraguan civil war and how the Rwandan civil war spilled over into the Democratic Republic of the Congo, fostering a regional war. He also looks at other cross-border insurgencies, such as those of the Kurdish PKK and Taliban fighters in Pakistan. Salehyan reveals that external sanctuaries feature in the political history of more than half of the world's armed insurgencies since 1945, and are also important in fostering state-to-state conflicts. Rebels who are unable to challenge the state on its own turf look for mobilization opportunities abroad. Neighboring states that are too weak to prevent rebel access, states that wish to foster instability in their rivals, and large refugee diasporas provide important opportunities for insurgent groups to establish external bases. Such sanctuaries complicate intelligence gathering, counterinsurgency operations, and efforts at peacemaking. States that host rebels intrude into negotiations between governments and opposition movements and can block progress toward peace when they pursue their own agendas.

In Stories without Borders, Julia Sonnevend considers the ways in which we recount and remember news stories of historic significance. Focusing on the Berlin Wall and on subsequent retellings of the event in a variety of ways - from Legoland reenactments to slabs of the Berlin Wall installed in global cities - Sonnevend discusses how certain events become built up into global iconic events.

A new approach to the metaphysics, background logic, and semantics of ontological debate, Ontology Without Borders offers new solutions to perennial philosophical puzzles about constitution and the nonexistent. Book jacket.