diff --git a/README.md b/README.md
index 161a6d5..ec89c7e 100644
--- a/README.md
+++ b/README.md
@@ -1,11 +1,63 @@
 csv-validator
 =============
 
-CSV validator library.
+CSV validator library
+
+That uses the constraints of Symfony framework: [http://symfony.com/doc/current/reference/constraints.html](http://symfony.com/doc/current/reference/constraints.html).
+
+Installation
+------------
+
+You need [composer]("https://getcomposer.org/"):
+
+	composer require deblan/csv-validator dev-master
 
-Works in progress. You should not use this package.
 
 Example
 -------
 
-Read the source of `example.php`.
+```
+<?php
+
+use Deblan\Csv\CsvParser;
+use Deblan\CsvValidator\Validator;
+use Symfony\Component\Validator\Validation;
+use Symfony\Component\Validator\Constraints\Email;
+use Symfony\Component\Validator\Constraints\Date;
+use Symfony\Component\Validator\Constraints\Callback;
+use Symfony\Component\Validator\Context\ExecutionContextInterface;
+
+require __DIR__.'/vendor/autoload.php';
+
+// Initialisation of the parser
+$parser = new CsvParser(__DIR__.'/tests/fixtures/example.csv');
+$parser->setHasLegend(true);
+
+// Initialisation of the validator
+$validator = new Validator($parser, Validation::createValidator());
+
+// The first field must contain an email
+$validator->addFieldConstraint(0, new Email());
+
+// The second field must contain a date
+$validator->addFieldConstraint(1, new Date());
+
+// An line must contain 3 columns
+$validator->addDataConstraint(new Callback(function($data, ExecutionContextInterface $context) {
+    if (count($data) !== 6) { // 6 because of the legend (3 fields * 2)
+        $context->addViolation('The line must contain 3 columns');
+    }
+}));
+
+$validator->validate();
+
+if ($validator->isValid() === false) {
+    foreach ($validator->getErrors() as $violation) {
+        $line = $violation->getLine(); 
+        $column = $violation->getColumn();
+        $message = $violation->getViolation()->getMessage();
+        
+        // Up to you!
+    }
+}
+```
diff --git a/example.php b/example.php
index 52713f5..9fb13a1 100644
--- a/example.php
+++ b/example.php
@@ -5,18 +5,31 @@ use Deblan\CsvValidator\Validator;
 use Symfony\Component\Validator\Validation;
 use Symfony\Component\Validator\Constraints\Email;
 use Symfony\Component\Validator\Constraints\Date;
+use Symfony\Component\Validator\Constraints\Callback;
+use Symfony\Component\Validator\Context\ExecutionContextInterface;
 
-chdir(__DIR__);
+require __DIR__.'/vendor/autoload.php';
 
-require 'vendor/autoload.php';
-
-$parser = new CsvParser('example.csv', ';', '');
+// Initialisation of the parser
+$parser = new CsvParser(__DIR__.'/tests/fixtures/example.csv');
+$parser->setHasLegend(true);
 
+// Initialisation of the validator
 $validator = new Validator($parser, Validation::createValidator());
 
+// The first field must contain an email
 $validator->addFieldConstraint(0, new Email());
+
+// The second field must contain a date
 $validator->addFieldConstraint(1, new Date());
 
+// An line must contain 3 columns
+$validator->addDataConstraint(new Callback(function($data, ExecutionContextInterface $context) {
+    if (count($data) !== 6) { // 6 because of the legend (3 fields * 2)
+        $context->addViolation('The line must contain 3 columns');
+    }
+}));
+
 $validator->validate();
 
 if ($validator->isValid() === false) {
@@ -24,14 +37,7 @@ if ($validator->isValid() === false) {
         $line = $violation->getLine(); 
         $column = $violation->getColumn();
         $message = $violation->getViolation()->getMessage();
-
-        echo <<<EOF
-Line   : $line
-Column : $column
-Message: $message
-
-
-EOF;
-
+        
+        // Up to you!
     }
 }
diff --git a/tests/ValidatorTest.php b/tests/ValidatorTest.php
new file mode 100644
index 0000000..50f28df
--- /dev/null
+++ b/tests/ValidatorTest.php
@@ -0,0 +1,86 @@
+<?php
+
+use Deblan\Csv\CsvParser;
+use Deblan\CsvValidator\Validator;
+use Symfony\Component\Validator\Validation;
+use Symfony\Component\Validator\Constraints\NotBlank;
+use Symfony\Component\Validator\Constraints\Email;
+
+class ValidatorTest extends \PHPUnit_Framework_TestCase
+{
+    public function testViolation()
+    {
+        $parser = $this->generateParser('example.csv');
+        $validator = $this->generateValidator($parser);
+        $this->setExpectedException('\RuntimeException');
+        $validator->isValid();
+    }
+    
+    public function testNoConstraint()
+    {
+        $parser = $this->generateParser('example.csv');
+        $validator = $this->generateValidator($parser);
+        $validator->validate();
+        $this->assertEquals(true, $validator->isValid());
+    }
+    
+    public function testFieldContraintsOk()
+    {
+        $parser = $this->generateParser('example.csv');
+        $validator = $this->generateValidator($parser);
+        $validator->addFieldConstraint(0, new NotBlank());
+        $validator->validate();
+        $this->assertEquals(true, $validator->isValid());
+        $this->assertEquals(0, count($validator->getErrors()));
+        
+        $parser = $this->generateParser('example.csv');
+        $validator = $this->generateValidator($parser);
+        $validator->addFieldConstraint(1, new NotBlank());
+        $validator->validate();
+        $this->assertEquals(true, $validator->isValid());
+        $this->assertEquals(0, count($validator->getErrors()));
+        
+        $parser = $this->generateParser('example.csv');
+        $validator = $this->generateValidator($parser);
+        $validator->addFieldConstraint(0, new NotBlank());
+        $validator->addFieldConstraint(1, new NotBlank());
+        $validator->validate();
+        $this->assertEquals(true, $validator->isValid());
+        $this->assertEquals(0, count($validator->getErrors()));
+    }
+    
+    public function testFieldContraintsKo()
+    {
+        $parser = $this->generateParser('example.csv');
+        $validator = $this->generateValidator($parser);
+        $validator->addFieldConstraint(0, new Email());
+        $validator->validate();
+        $this->assertEquals(false, $validator->isValid());
+        $this->assertEquals(4, count($validator->getErrors()));
+        
+        $parser = $this->generateParser('example.csv');
+        $validator = $this->generateValidator($parser);
+        $validator->addFieldConstraint(1, new Email());
+        $validator->validate();
+        $this->assertEquals(false, $validator->isValid());
+        $this->assertEquals(4, count($validator->getErrors()));
+        
+        $parser = $this->generateParser('example.csv');
+        $validator = $this->generateValidator($parser);
+        $validator->addFieldConstraint(0, new Email());
+        $validator->addFieldConstraint(1, new Email());
+        $validator->validate();
+        $this->assertEquals(false, $validator->isValid());
+        $this->assertEquals(8, count($validator->getErrors()));
+    }
+
+    protected function generateParser($file)
+    {
+        return new CsvParser(__DIR__.'/fixtures/'.$file);
+    }
+
+    protected function generateValidator(CsvParser $parser) 
+    {
+        return new Validator($parser, Validation::createValidator());
+    }
+}
diff --git a/tests/fixtures/example.csv b/tests/fixtures/example.csv
new file mode 100644
index 0000000..7cadbe7
--- /dev/null
+++ b/tests/fixtures/example.csv
@@ -0,0 +1,4 @@
+"foo";"bar"
+"foo1";"bar1"
+"foo2";"bar2"
+"foo3";"bar3"