- Variations on a theme by Ribet - slides from my lecture at the 2015 AMS Summer Institute on Algebraic Geometry

- Galois Theory: Past and Present - slides from a colloquium lecture on the occasion of the 200th anniversary of Galois' birth, 2010-11

- Dualité arithmétique pour les 1-motifs - slides from my lecture at the conference in honour of Luc Illusie (Orsay, 2005) (with English subtitles)

- A writeup (dvi file) of a 2000 January expository lecture in Luminy (for a never-to-appear proceedings) on the construction of Voevodsky's triangulated category DM of mixed motivic complexes and the embedding of the category of effective `geometrical' motives into it.

- The streaming video of my lecture at the Galois bicentenary conference (Institut Henri Poincaré, Paris) in October 2011: "Grothendieck et la théorie de Galois".

- The streaming video of a lecture at the Isaac Newton Institute (Cambridge, UK) in July 2009 on "Grothendieck's Section Conjecture and zero-cycles on varieties".

- The streaming video of a lecture at MSRI in August 1999 on "Introduction to Anabelian Geometry" (poorer quality than the previous one).

- Lectures on Linear Algebraic Groups
Notes from a 2006 course, revised in 2012.

- Cohomology of coherent sheaves
Notes for part of a 2011 course on schemes.

- First Steps in Local Algebra
Notes for part of a 2010 graduate course.

- Dedekind schemes (pdf file)
These are notes from part of an earlier course (1999/2000) on fundamental groups, treating the basic ramification theory of Dedekind schemes. This material was not incorporated in my book on the subject and has not been revised.

- Schemes: the beginnings
This also comes from notes for an old course (1999/2000) on fundamental groups, not incorporated in my book on the subject.