diff --git a/src/core/codec.rs b/src/core/codec.rs
index c93a6d22f..c6991b1d6 100644
--- a/src/core/codec.rs
+++ b/src/core/codec.rs
@@ -38,8 +38,9 @@ impl SimpleSegmentSerializer {
 
 impl SegmentSerializer<()> for SimpleSegmentSerializer {
 
-    fn store_doc(&mut self, field: &mut Iterator<Item=&FieldValue>) {
-
+    fn store_doc(&mut self, field_values_it: &mut Iterator<Item=&FieldValue>) {
+        let field_values: Vec<&FieldValue> = field_values_it.collect();
+        self.store_writer.store(&field_values);
     }
 
     fn new_term(&mut self, term: &Term, doc_freq: DocId) -> Result<()> {
diff --git a/src/core/error.rs b/src/core/error.rs
index c820cd7c7..dd649c81a 100644
--- a/src/core/error.rs
+++ b/src/core/error.rs
@@ -1,11 +1,13 @@
 use std::result;
 use std::io;
+use byteorder;
 
 #[derive(Debug)]
 pub enum Error {
     NotImplementedYet,
     WriteError(String),
     ReadError,
+    BinaryReadError(byteorder::Error),
     IOError(io::ErrorKind, String),
     FileNotFound(String),
     LockError(String),
diff --git a/src/core/schema.rs b/src/core/schema.rs
index b0cd6c8c0..db8d37431 100644
--- a/src/core/schema.rs
+++ b/src/core/schema.rs
@@ -1,5 +1,6 @@
 use core::global::*;
-use std::fmt::Write;
+use core::error;
+use std::io::Write;
 use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
 use std::string::FromUtf8Error;
 use std::collections::HashMap;
@@ -7,6 +8,8 @@ use std::str;
 use std::iter;
 use std::slice;
 use std::fmt;
+use std::io::Read;
+use core::serialize::BinarySerializable;
 
 
 
@@ -57,6 +60,37 @@ pub struct FieldValue {
 }
 
 
+impl BinarySerializable for Field {
+    fn serialize(&self, writer: &mut Write) -> error::Result<usize> {
+        let Field(field_id) = *self;
+        field_id.serialize(writer)
+    }
+
+    fn deserialize(reader: &mut Read) -> error::Result<Field> {
+        u8::deserialize(reader).map(Field)
+    }
+}
+
+
+impl BinarySerializable for FieldValue {
+    fn serialize(&self, writer: &mut Write) -> error::Result<usize> {
+        Ok(
+            try!(self.field.serialize(writer)) +
+            try!(self.text.serialize(writer))
+        )
+    }
+    fn deserialize(reader: &mut Read) -> error::Result<Self> {
+        let field = try!(Field::deserialize(reader));
+        let text = try!(String::deserialize(reader));
+        Ok(FieldValue {
+            field: field,
+            text: text,
+        })
+    }
+}
+
+
+
 #[derive(Clone,PartialEq,PartialOrd,Ord,Eq,Hash)]
 pub struct Term {
     data: Vec<u8>,
diff --git a/src/core/serialize.rs b/src/core/serialize.rs
index f66e761cb..6b9ded357 100644
--- a/src/core/serialize.rs
+++ b/src/core/serialize.rs
@@ -3,6 +3,8 @@ use byteorder::{BigEndian, ReadBytesExt, WriteBytesExt};
 use std::fmt;
 use std::io::Write;
 use core::error;
+use core::error::Error;
+use std::io::Cursor;
 use std::io::Read;
 
 pub trait BinarySerializable : fmt::Debug + Sized {
@@ -22,18 +24,15 @@ impl BinarySerializable for () {
 
 impl<T: BinarySerializable> BinarySerializable for Vec<T> {
     fn serialize(&self, writer: &mut Write) -> error::Result<usize> {
-        let mut total_size = 0;
-        writer.write_u32::<BigEndian>(self.len() as u32);
-        total_size += 4;
+        let num_elements = self.len() as u32;
+        let mut total_size = try!(num_elements.serialize(writer));
         for it in self.iter() {
-            let item_size = try!(it.serialize(writer));
-            total_size += item_size;
+            total_size += try!(it.serialize(writer));
         }
         Ok(total_size)
     }
     fn deserialize(reader: &mut Read) -> error::Result<Vec<T>> {
-        // TODO error
-        let num_items = reader.read_u32::<BigEndian>().unwrap();
+        let num_items = try!(u32::deserialize(reader));
         let mut items: Vec<T> = Vec::with_capacity(num_items as usize);
         for _ in 0..num_items {
             let item = try!(T::deserialize(reader));
@@ -42,3 +41,128 @@ impl<T: BinarySerializable> BinarySerializable for Vec<T> {
         Ok(items)
     }
 }
+
+impl BinarySerializable for u32 {
+    fn serialize(&self, writer: &mut Write) -> error::Result<usize> {
+        writer.write_u32::<BigEndian>(self.clone())
+              .map(|x| 4)
+              .map_err(Error::BinaryReadError)
+    }
+    fn deserialize(reader: &mut Read) -> error::Result<u32> {
+        reader.read_u32::<BigEndian>()
+              .map_err(Error::BinaryReadError)
+    }
+}
+
+
+impl BinarySerializable for u8 {
+    fn serialize(&self, writer: &mut Write) -> error::Result<usize> {
+        // TODO error
+        writer.write_u8(self.clone());
+        Ok(1)
+    }
+    fn deserialize(reader: &mut Read) -> error::Result<u8> {
+        reader.read_u8()
+              .map_err(Error::BinaryReadError)
+    }
+}
+
+impl BinarySerializable for String {
+    fn serialize(&self, writer: &mut Write) -> error::Result<usize> {
+        // TODO error
+        let data: &[u8] = self.as_bytes();
+        let mut size = try!((data.len() as u32).serialize(writer));
+        size += data.len();
+        writer.write_all(data);
+        Ok(size)
+    }
+
+    fn deserialize(reader: &mut Read) -> error::Result<String> {
+        // TODO error
+        let string_length = try!(u32::deserialize(reader)) as usize;
+        let mut result = String::with_capacity(string_length);
+        reader.take(string_length as u64).read_to_string(&mut result);
+        Ok(result)
+    }
+}
+
+
+#[test]
+fn test_serialize_u8() {
+    let mut buffer: Vec<u8> = Vec::new();
+    {
+        let x: u8 = 3;
+        x.serialize(&mut buffer);
+        assert_eq!(buffer.len(), 1);
+    }
+    {
+        let x: u8 = 5;
+        x.serialize(&mut buffer);
+        assert_eq!(buffer.len(), 2);
+    }
+    let mut cursor = Cursor::new(&buffer);
+    assert_eq!(3, u8::deserialize(&mut cursor).unwrap());
+    assert_eq!(5, u8::deserialize(&mut cursor).unwrap());
+    assert!(u8::deserialize(&mut cursor).is_err());
+}
+
+
+#[test]
+fn test_serialize_u32() {
+    let mut buffer: Vec<u8> = Vec::new();
+    {
+        let x: u32 = 3;
+        x.serialize(&mut buffer);
+        assert_eq!(buffer.len(), 4);
+    }
+    {
+        let x: u32 = 5;
+        x.serialize(&mut buffer);
+        assert_eq!(buffer.len(), 8);
+    }
+    let mut cursor = Cursor::new(&buffer);
+    assert_eq!(3, u32::deserialize(&mut cursor).unwrap());
+    assert_eq!(5, u32::deserialize(&mut cursor).unwrap());
+    assert!(u32::deserialize(&mut cursor).is_err());
+}
+
+
+
+#[test]
+fn test_serialize_string() {
+    let mut buffer: Vec<u8> = Vec::new();
+    let first_length = 4 + 3 * 4;
+    let second_length = 4 + 3 * 8;
+    {
+        let x: String = String::from("ぽよぽよ");
+        assert_eq!(x.serialize(&mut buffer).unwrap(), first_length);
+        assert_eq!(buffer.len(), first_length);
+    }
+    {
+        let x: String = String::from("富士さん見える。");
+        assert_eq!(x.serialize(&mut buffer).unwrap(), second_length);
+        assert_eq!(buffer.len(), first_length + second_length);
+    }
+    let mut cursor = Cursor::new(&buffer);
+    assert_eq!("ぽよぽよ", String::deserialize(&mut cursor).unwrap());
+    assert_eq!("富士さん見える。", String::deserialize(&mut cursor).unwrap());
+    assert!(u32::deserialize(&mut cursor).is_err());
+}
+
+
+
+#[test]
+fn test_serialize_vec() {
+    let mut buffer: Vec<u8> = Vec::new();
+    let first_length = 4 + 3 * 4;
+    let second_length = 4 + 3 * 8;
+    let vec = vec!(String::from("ぽよぽよ"), String::from("富士さん見える。"));
+    assert_eq!(vec.serialize(&mut buffer).unwrap(), first_length + second_length + 4);
+    let mut cursor = Cursor::new(&buffer);
+    {
+        let deser: Vec<String> = Vec::deserialize(&mut cursor).unwrap();
+        assert_eq!(deser.len(), 2);
+        assert_eq!("ぽよぽよ", deser[0]);
+        assert_eq!("富士さん見える。", deser[1]);
+    }
+}
diff --git a/src/core/skip.rs b/src/core/skip.rs
index 65c73ef1c..a143fa6fe 100644
--- a/src/core/skip.rs
+++ b/src/core/skip.rs
@@ -65,7 +65,7 @@ impl<T: BinarySerializable> LayerBuilder<T> {
 }
 
 
-// 
+//
 // fn display_layer<'a, T: BinarySerializable>(layer: &mut Layer<'a, T>) {
 //     for it in layer {
 //         println!(" - {:?}", it);
@@ -146,20 +146,6 @@ impl<T: BinarySerializable> SkipListBuilder<T> {
 }
 
 
-impl BinarySerializable for u32 {
-    fn serialize(&self, writer: &mut Write) -> error::Result<usize> {
-        // TODO error handling
-        writer.write_u32::<BigEndian>(self.clone());
-        Ok(4)
-    }
-
-    fn deserialize(reader: &mut Read) -> error::Result<Self> {
-        // TODO error handling
-        reader.read_u32::<BigEndian>().map_err(|err| error::Error::ReadError)
-    }
-}
-
-
 struct Layer<'a, T> {
     cursor: Cursor<&'a [u8]>,
     next_id: DocId,
diff --git a/src/core/store.rs b/src/core/store.rs
index 269079a08..bba90a2fb 100644
--- a/src/core/store.rs
+++ b/src/core/store.rs
@@ -2,8 +2,14 @@ use std::io::BufWriter;
 use std::fs::File;
 use core::schema::Document;
 use core::schema::FieldValue;
+use core::error;
+use core::serialize::BinarySerializable;
+use std::io::Write;
+use std::io::Read;
 
 pub struct StoreWriter {
+    doc: usize,
+    offsets: Vec<usize>,
     writer: BufWriter<File>,
 }
 
@@ -11,13 +17,31 @@ impl StoreWriter {
 
     pub fn new(file: File) -> StoreWriter {
         StoreWriter {
+            doc: 0,
+            offsets: Vec::new(),
             writer: BufWriter::new(file),
         }
     }
 
-    pub fn store(&mut self, fields: &mut Iterator<Item=&FieldValue>) {
-        for field in fields {
-            println!("{:?}", field);
-        }
+    pub fn store(&mut self, fields: &Vec<&FieldValue>) {
+        
+        self.doc += 1;
     }
+
 }
+
+
+
+
+// impl<T: BinarySerializable> BinarySerializable for Vec<T> {
+//     fn serialize(&self, field_values: &mut Iterator<Item=&FieldValue>) -> error::Result<usize> {
+//         let mut total_size = 0;
+//         writer.write_u32::<BigEndian>(self.len() as u32);
+//         total_size += 4;
+//         for it in self.iter() {
+//             let item_size = try!(it.serialize(writer));
+//             total_size += item_size;
+//         }
+//         Ok(total_size)
+//     }
+// }
diff --git a/src/core/writer.rs b/src/core/writer.rs
index 4f60a51b4..e9767fa4e 100644
--- a/src/core/writer.rs
+++ b/src/core/writer.rs
@@ -158,11 +158,11 @@ impl SegmentWriter {
 				}
 			}
 		}
-		let mut stored_field_it = doc.fields().filter(|field_value| {
+		let mut stored_fieldvalues_it = doc.fields().filter(|field_value| {
 			schema.get_field(&field_value.field)
 				  .is_stored()
 		});
-		self.segment_serializer.store_doc(&mut stored_field_it);
+		self.segment_serializer.store_doc(&mut stored_fieldvalues_it);
         self.max_doc += 1;
     }