What are Endophytes? -- What are Endophytes? -- Endophytic Bacteria -- Spectrum and Population Dynamics of Bacterial Root Endophytes -- Bacterial Endophytes as Elicitors of Induced Systemic Resistance -- Control of Plant Pathogenic Fungi with Bacterial Endophytes -- Role of Proteins Secreted by Rhizobia in Symbiotic Interactions with Leguminous Roots -- Research on Endophytic Bacteria: Recent Advances with Forest Trees -- Endophytic Fungi -- Biodiversity of Fungal Root-Endophyte Communities and Populations, in Particular of the Dark Septate Endophyte Phialocephala fortinii s. l. -- Endophytic Root Colonization by Fusarium Species: Histology, Plant Interactions, and Toxicity -- Microbial Endophytes of Orchid Roots -- Fungal Endophytes in Submerged Roots -- Nematophagous Fungi as Root Endophytes -- Molecular Diversity and Ecological Roles of Mycorrhiza-Associated Sterile Fungal Endophytes in Mediterranean Ecosystems -- Oidiodendron maius: Saprobe in Sphagnum Peat, Mutualist in Ericaceous Roots? -- Mycorrhizal and Endophytic Fungi of Epacrids (Ericaceae) -- Mutualistic Interactions with Fungal Root Endophytes -- Understanding the Roles of Multifunctional Mycorrhizal and Endophytic Fungi -- Methods -- Isolation Procedures for Endophytic Microorganisms -- Microbial Interactions with Plants: a Hidden World? -- Application of Molecular Fingerprinting Techniques to Explore the Diversity of Bacterial Endophytic Communities.