Dujella, Andrej  
   University of Zagreb, Croatia. Page on Diophantine m-tuples; Tables of high-rank elliptic curves; Link to mathematical departments and number theory groups and seminars; Information for students on courses in number theory and cryptography.
   http://www.math.hr/~duje/

Darmon, Henri  
   McGill University. Algebraic number theory, with a special emphasis on elliptic curves, modular forms, and their associated L-functions.
   http://www.math.mcgill.ca/~darmon/

Doud, Darrin  
   Brigham Young University. Cohomology of arithmetic groups, Galois representations. Papers, resources.
   http://www.math.byu.edu/~doud/

Dickinson, Mark  
   University of Pittsburgh. Contact, teaching information.
   http://www.pitt.edu/AFShome/d/i/dickinsm/public/html/

Drinen, Michael  
   Willamette University. Iwasawa theory and elliptic curves. Publications, teaching material.
   http://www.willamette.edu/~mdrinen/

Dickinson, Detta  
   NUI Maynooth. Measure theory and metric Diophantine approximation: Diophantine approximation on manifolds.
   http://www.maths.may.ie/staff/ddickinson/

David, Chantal  
   Concordia University, Montréal. Drinfeld modules, Galois representations. Publications, talks.
   http://cicma.mathstat.concordia.ca/faculty/chantal/

Dummigan, Neil  
   University of Sheffield. Arithmetical algebraic geometry. Publications.
   http://www.shef.ac.uk/personal/n/neildummiganshomepage/

Deanin, Alice  
   Villanova University. Computational number theory and Diophantine approximation. Teaching material, resources.
   http://www19.homepage.villanova.edu/alice.deanin/

Dodson, Maurice  
   University of York. Metrical Diophantine approximation, harmonic analysis and applications to signal processing, chaos and biology. Publications, teaching material.
   http://www-users.york.ac.uk/~mmd1/

Doche, Christophe  
   Macquarie University, Sydney. Analytic and algorithmic number theory: Mahler measure and Lehmer's problem; Rudin-Shapiro polynomials. Publications, thesis, Pari/GP code.
   http://www.math.u-bordeaux.fr/~cdoche/indexeng.html

Duke, William  
   University of California Los Angeles. Number theory and automorphic forms. Publications.
   http://www.math.ucla.edu/~duke/

Duquesne, Sylvain  
   Université Montpellier II. Arithmetic and algorithmic number theory and applications in cryptography; arithmetic of curves of genus 2 or higher. Publications, software.
   http://www.math.univ-montp2.fr/~duquesne/anglais/

Dokchitser, Tim  
   University of Durham. Arithmetic algebraic geometry. Publications, thesis, Pari/GP software.
   http://maths.dur.ac.uk/~dma0td/

Dorman, David R.  
   Middlebury College. Algebraic Number Theory and Arithmetical Algebraic Geometry. Contact information.
   http://community.middlebury.edu/~dorman/

Damianou, Pantelis  
   University of Cyprus. Lie Groups; Integrable Systems; Poisson Geometry; Number Theory. Publications, talks.
   http://www.ucy.ac.cy/~damianou/

Daniel, Stephan  
   University of Cardiff. Analytic number theory. Publications.
   http://www.cf.ac.uk/maths/daniels1/

Denef, Jan  
   University of Leuven. Number Theory, Algebraic Geometry, Singularity Theory and Mathematical Logic. Publications, software.
   http://www.wis.kuleuven.ac.be/algebra/denef.html

Dresden, Greg  
   Washington and Lee University. Mahler measure of polynomials. Publications.
   http://home.wlu.edu/~dresdeng/

Diaz y Diaz, Francisco  
   Université Bordeaux I. Computations in number fields. Preprints.
   http://www.math.u-bordeaux.fr/~diaz/

Deng An-Wen  
   Academica Sinica, Taiwan. Number Theory and Algebraic Geometry. Publications.
   http://www.sinica.edu.tw/math/html/post-doc/deng-e.html

Dienst, Thilo  
   Universität Dortmund. Geometry of Numbers; Polytopes; Quadratic Forms; Diophantine Approximation; History of Mathematics. Publications, thesis, resources.
   http://www.matha.mathematik.uni-dortmund.de/~thilo/

Diem, Claus  
   Institute for Experimental Mathematics, University of Essen. Arithmetic algebraic geometry: structure and arithmetic of abelian varieties; discrete logarithm problems; the regular inverse Galois problem. Publications, thesis.
   http://www.exp-math.uni-essen.de/~diem/english.html

Diamond, Fred  
   Brandeis University. Modular forms and Galois representations. CV, publications and preprints.
   http://www.math.brandeis.edu/homepages/diamond/

Diamond, Harold G.  
   University of Illinois at Urbana-Champaign. Analytic number theory, distribution of primes, arithmetic functions, sieve methods. Publications.
   http://www.math.uiuc.edu/~diamond/

Deligne, Pierre  
   Institute for Advanced Study. Publications, preprints.
   http://www.math.ias.edu/~phares/deligne/Deligne.html

Drmota, Michael  
   Institut für Diskrete Mathematik und Geometrie, TU Wien. Number Theory; Combinatorial Enumeration and Analysis of Algorithms; Stochastic Processes in Combinatorial Structures. Publications, teaching.
   http://www.dmg.tuwien.ac.at/drmota/

Dummit, David S.  
   University of Vermont. Algebraic number theory, arithmetic algebraic geometry, computational mathematics.
   http://www.emba.uvm.edu/EM/Math/faculty/dummit/dummit.html