diff --git a/README.md b/README.md
index fce6221..21014f7 100644
--- a/README.md
+++ b/README.md
@@ -10,6 +10,7 @@
 | (Extended) XYZ | .xyz      |
 | PDB            | .pdb      |
 | SDF            | .sdf      |
+| XTC            | .xtc      |
 
 This project is a Rust port of [`chemfiles`](https://github.com/chemfiles/chemfiles/), a modern C++ library with the same purpose.
 
diff --git a/src/format.rs b/src/format.rs
index b3380be..877da69 100644
--- a/src/format.rs
+++ b/src/format.rs
@@ -7,6 +7,7 @@
 use crate::error::CError;
 use crate::formats::pdb::PDBFormat;
 use crate::formats::sdf::SDFFormat;
+use crate::formats::xtc::XTCFormat;
 use crate::formats::xyz::XYZFormat;
 use crate::frame::Frame;
 use std::fs::File;
@@ -18,6 +19,7 @@ use std::path::Path;
 /// - `XYZ`: plain-text XYZ coordinate format.
 /// - `PDB`: Protein Data Bank format.
 /// - `SDF`: Structure Data File format.
+/// - `XTC`: GROMACS' portable format for trajectories.
 /// - `Guess`: autodetect format from file extension.
 #[derive(Clone, Copy)]
 pub enum TextFormat {
@@ -27,6 +29,8 @@ pub enum TextFormat {
     PDB,
     /// SDF file format.
     SDF,
+    /// XTC file format.
+    XTC,
     /// Automatically detect format from file extension.
     Guess,
 }
@@ -39,6 +43,8 @@ pub enum Format<'a> {
     PDB(PDBFormat<'a>),
     /// Handler for the SDF format.
     SDF(SDFFormat),
+    /// Handler for the XTC format.
+    XTC(XTCFormat),
 }
 
 impl Format<'_> {
@@ -54,6 +60,7 @@ impl Format<'_> {
             "xyz" => Ok(Format::XYZ(XYZFormat)),
             "pdb" => Ok(Format::PDB(PDBFormat::new())),
             "sdf" => Ok(Format::SDF(SDFFormat)),
+            "xtc" => Ok(Format::XTC(XTCFormat)),
             _ => Err(CError::GenericError("unknown file format".to_string())),
         }
     }
@@ -69,6 +76,7 @@ impl Format<'_> {
             TextFormat::XYZ => Ok(Format::XYZ(XYZFormat)),
             TextFormat::PDB => Ok(Format::PDB(PDBFormat::new())),
             TextFormat::SDF => Ok(Format::SDF(SDFFormat)),
+            TextFormat::XTC => Ok(Format::XTC(XTCFormat)),
             TextFormat::Guess => Self::new(path),
         }
     }
@@ -120,6 +128,7 @@ impl FileFormat for Format<'_> {
             Format::XYZ(format) => format.read_next(reader),
             Format::PDB(format) => format.read_next(reader),
             Format::SDF(format) => format.read_next(reader),
+            Format::XTC(format) => format.read_next(reader),
         }
     }
 
@@ -128,6 +137,7 @@ impl FileFormat for Format<'_> {
             Format::XYZ(format) => format.read(reader),
             Format::PDB(format) => format.read(reader),
             Format::SDF(format) => format.read(reader),
+            Format::XTC(format) => format.read(reader),
         }
     }
 
@@ -136,6 +146,7 @@ impl FileFormat for Format<'_> {
             Format::XYZ(format) => format.write_next(writer, frame),
             Format::PDB(format) => format.write_next(writer, frame),
             Format::SDF(format) => format.write_next(writer, frame),
+            Format::XTC(format) => format.write_next(writer, frame),
         }
     }
 
@@ -144,6 +155,7 @@ impl FileFormat for Format<'_> {
             Format::XYZ(format) => format.forward(reader),
             Format::PDB(format) => format.forward(reader),
             Format::SDF(format) => format.forward(reader),
+            Format::XTC(format) => format.forward(reader),
         }
     }
 
@@ -152,6 +164,7 @@ impl FileFormat for Format<'_> {
             Format::XYZ(format) => format.finalize(writer),
             Format::PDB(format) => format.finalize(writer),
             Format::SDF(format) => format.finalize(writer),
+            Format::XTC(format) => format.finalize(writer),
         }
     }
 }
diff --git a/src/formats.rs b/src/formats.rs
index b38f7ff..c425c7e 100644
--- a/src/formats.rs
+++ b/src/formats.rs
@@ -1,4 +1,5 @@
 pub mod pdb;
 pub mod pdb_connectivity;
 pub mod sdf;
+pub mod xtc;
 pub mod xyz;
diff --git a/src/formats/xtc.rs b/src/formats/xtc.rs
new file mode 100644
index 0000000..6110d49
--- /dev/null
+++ b/src/formats/xtc.rs
@@ -0,0 +1,32 @@
+use std::{
+    fs::File,
+    io::{BufRead, BufReader, BufWriter, Write},
+};
+
+use crate::{error::CError, format::FileFormat, frame::Frame};
+
+pub struct XTCFormat;
+
+impl XTCFormat {}
+
+impl FileFormat for XTCFormat {
+    fn read_next(&mut self, reader: &mut BufReader<File>) -> Result<Frame, CError> {
+        todo!();
+    }
+
+    fn read(&mut self, reader: &mut BufReader<File>) -> Result<Option<Frame>, CError> {
+        todo!();
+    }
+
+    fn write_next(&mut self, writer: &mut BufWriter<File>, frame: &Frame) -> Result<(), CError> {
+        todo!();
+    }
+
+    fn forward(&self, reader: &mut BufReader<File>) -> Result<Option<u64>, CError> {
+        todo!();
+    }
+
+    fn finalize(&self, writer: &mut BufWriter<File>) -> Result<(), CError> {
+        todo!();
+    }
+}