diff --git a/libimagentrycategory/Cargo.toml b/libimagentrycategory/Cargo.toml
index a14799fe..d2439728 100644
--- a/libimagentrycategory/Cargo.toml
+++ b/libimagentrycategory/Cargo.toml
@@ -14,3 +14,13 @@ repository    = "https://github.com/matthiasbeyer/imag"
 homepage      = "http://imag-pim.org"
 
 [dependencies]
+toml = "0.4"
+toml-query = "0.2"
+is-match = "0.1"
+
+[dependencies.libimagerror]
+path = "../libimagerror"
+
+[dependencies.libimagstore]
+path = "../libimagstore"
+
diff --git a/libimagentrycategory/src/category.rs b/libimagentrycategory/src/category.rs
new file mode 100644
index 00000000..b47282a0
--- /dev/null
+++ b/libimagentrycategory/src/category.rs
@@ -0,0 +1,94 @@
+//
+// imag - the personal information management suite for the commandline
+// Copyright (C) 2015, 2016 Matthias Beyer <mail@beyermatthias.de> and contributors
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; version
+// 2.1 of the License.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+//
+
+use toml_query::insert::TomlValueInsertExt;
+use toml_query::read::TomlValueReadExt;
+use toml_query::error::ErrorKind as TQEK;
+use toml::Value;
+
+use libimagstore::store::Entry;
+use libimagerror::into::IntoError;
+
+use error::CategoryErrorKind as CEK;
+use error::MapErrInto;
+use result::Result;
+
+#[derive(Clone, Debug, Eq, PartialEq, Ord, PartialOrd)]
+pub struct Category(String);
+
+impl From<String> for Category {
+
+    fn from(s: String) -> Category {
+        Category(s)
+    }
+
+}
+
+impl Into<String> for Category {
+    fn into(self) -> String {
+        self.0
+    }
+}
+
+pub trait EntryCategory {
+
+    fn set_category(&mut self, s: Category) -> Result<()>;
+    fn get_category(&self) -> Result<Option<Category>>;
+
+    fn has_category(&self) -> Result<bool>;
+
+}
+
+impl EntryCategory for Entry {
+
+    fn set_category(&mut self, s: Category) -> Result<()> {
+        self.get_header_mut()
+            .insert(&String::from("category.value"), Value::String(s.into()))
+            .map_err_into(CEK::HeaderWriteError)
+            .map(|_| ())
+    }
+
+    fn get_category(&self) -> Result<Option<Category>> {
+        match self.get_header().read(&String::from("category.value")) {
+            Err(res) => match res.kind() {
+                &TQEK::IdentifierNotFoundInDocument(_) => Ok(None),
+                _                                      => Err(res),
+            }
+            .map_err_into(CEK::HeaderReadError),
+
+            Ok(&Value::String(ref s)) => Ok(Some(s.clone().into())),
+            Ok(_) => Err(CEK::TypeError.into_error()).map_err_into(CEK::HeaderReadError),
+        }
+    }
+
+    fn has_category(&self) -> Result<bool> {
+        let res = self.get_header().read(&String::from("category.value"));
+        if res.is_err() {
+            let res = res.unwrap_err();
+            match res.kind() {
+                &TQEK::IdentifierNotFoundInDocument(_) => Ok(false),
+                _                                      => Err(res),
+            }
+            .map_err_into(CEK::HeaderReadError)
+        } else {
+            Ok(true)
+        }
+    }
+
+}
diff --git a/libimagentrycategory/src/error.rs b/libimagentrycategory/src/error.rs
new file mode 100644
index 00000000..17bc4543
--- /dev/null
+++ b/libimagentrycategory/src/error.rs
@@ -0,0 +1,31 @@
+//
+// imag - the personal information management suite for the commandline
+// Copyright (C) 2015, 2016 Matthias Beyer <mail@beyermatthias.de> and contributors
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; version
+// 2.1 of the License.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+//
+
+generate_error_module!(
+    generate_error_types!(CategoryError, CategoryErrorKind,
+        HeaderReadError  => "Header read error",
+        HeaderWriteError => "Header write error",
+        TypeError        => "Found wrong type in header"
+    );
+);
+
+pub use self::error::CategoryError;
+pub use self::error::CategoryErrorKind;
+pub use self::error::MapErrInto;
+
diff --git a/libimagentrycategory/src/lib.rs b/libimagentrycategory/src/lib.rs
index cdfbe1aa..8a9c867a 100644
--- a/libimagentrycategory/src/lib.rs
+++ b/libimagentrycategory/src/lib.rs
@@ -1,6 +1,30 @@
-#[cfg(test)]
-mod tests {
-    #[test]
-    fn it_works() {
-    }
-}
+//
+// imag - the personal information management suite for the commandline
+// Copyright (C) 2015, 2016 Matthias Beyer <mail@beyermatthias.de> and contributors
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; version
+// 2.1 of the License.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+//
+
+extern crate toml_query;
+extern crate toml;
+
+#[macro_use]
+extern crate libimagerror;
+extern crate libimagstore;
+
+pub mod category;
+pub mod error;
+pub mod result;
+
diff --git a/libimagentrycategory/src/result.rs b/libimagentrycategory/src/result.rs
new file mode 100644
index 00000000..517d0e96
--- /dev/null
+++ b/libimagentrycategory/src/result.rs
@@ -0,0 +1,26 @@
+
+//
+// imag - the personal information management suite for the commandline
+// Copyright (C) 2015, 2016 Matthias Beyer <mail@beyermatthias.de> and contributors
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; version
+// 2.1 of the License.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+//
+
+use std::result::Result as RResult;
+
+use error::CategoryError;
+
+pub type Result<T> = RResult<T, CategoryError>;
+