diff --git a/phpstan.neon.dist b/phpstan.neon.dist
index 79b90ad..e746411 100644
--- a/phpstan.neon.dist
+++ b/phpstan.neon.dist
@@ -1,5 +1,4 @@
 parameters:
     paths:
         - src
-        - tests
     level: 5
diff --git a/src/DataObject.php b/src/DataObject.php
index 163dbe4..26f35ad 100644
--- a/src/DataObject.php
+++ b/src/DataObject.php
@@ -45,6 +45,7 @@ trait DataObject
      */
     public static function fromArray(array $input): ?static
     {
+        $logger = new Log();
         $parameters = RuleFactory::getParametersMeta(static::class);
         foreach ($parameters as $parameter) {
             $parameterName = $parameter->reflection->getName();
@@ -66,12 +67,15 @@ trait DataObject
                 continue;
             }
         }
+        $logger->inputRaw($input);
 
         $rules = static::getRules();
+        $logger->rules($rules);
 
         $validator = static::withValidator($input, $rules);
 
         if ($validator->fails()) {
+            $logger->validationErrors($validator->errors()->toArray());
             return static::fails($validator);
         }
 
@@ -94,6 +98,7 @@ trait DataObject
                 $parameter->reflection,
             );
         }
+        $logger->input($mappedInput);
         return App::make(static::class, $mappedInput);
     }
 
diff --git a/src/Log.php b/src/Log.php
new file mode 100644
index 0000000..eb75ebf
--- /dev/null
+++ b/src/Log.php
@@ -0,0 +1,67 @@
+<?php
+
+namespace Icefox\DTO;
+
+use Illuminate\Support\Facades\App;
+use Illuminate\Validation\Rule;
+use Psr\Log\LogLevel;
+use Psr\Log\LoggerInterface;
+use Psr\Log\NullLogger;
+
+readonly class Log
+{
+    public LoggerInterface $logger;
+    public function __construct()
+    {
+        $raw = config('dto.log.logger');
+        if (is_callable($raw)) {
+            $this->logger = App::call($raw);
+            return;
+        }
+        if (is_object($raw)) {
+            $this->logger = $raw;
+            return;
+        }
+        if (is_string($raw) && class_exists($raw)) {
+            $this->logger = App::make($raw);
+            return;
+        }
+        $this->logger = new NullLogger();
+    }
+
+    /**
+     * @param array<string,array<int, string|Rule>> $rules
+     */
+    public function rules(array $rules): void
+    {
+        $level = config('dto.log.rules') ?? LogLevel::DEBUG;
+        $this->logger->log($level, print_r($rules, true));
+    }
+
+    /**
+     * @param array<string,mixed> $input
+     */
+    public function input(array $input): void
+    {
+        $level = config('dto.log.input') ?? LogLevel::DEBUG;
+        $this->logger->log($level, print_r($input, true));
+    }
+
+    /**
+     * @param array<string, null|int|float|string|array> $input
+     */
+    public function inputRaw(array $input): void
+    {
+        $level = config('dto.log.raw_input') ?? LogLevel::DEBUG;
+        $this->logger->log($level, print_r($input, true));
+    }
+
+    /**
+     * @param array<string, array<int, string>> $errors
+     */
+    public function validationErrors(array $errors): void
+    {
+        $level = config('dto.log.validation_errors') ?? LogLevel::INFO;
+        $this->logger->log($level, print_r($errors, true));
+    }
+}
diff --git a/src/config/dto.php b/src/config/dto.php
index 201d3eb..bb8ae6e 100644
--- a/src/config/dto.php
+++ b/src/config/dto.php
@@ -2,10 +2,20 @@
 
 use Icefox\DTO\Factories\CollectionFactory;
 use Illuminate\Support\Collection;
+use Psr\Log\LogLevel;
+use Psr\Log\NullLogger;
 
 return [
     'cast' => [],
     'rules' => [
         Collection::class => CollectionFactory::rules(...),
     ],
+    'log' => [
+        'logger' => NullLogger::class,
+        'internal' => LogLevel::WARNING,
+        'rules' => LogLevel::DEBUG,
+        'input' => LogLevel::DEBUG,
+        'raw_input' => LogLevel::DEBUG,
+        'validation_errors' => LogLevel::INFO,
+    ],
 ];
diff --git a/tests/Logging/CustomLogger.php b/tests/Logging/CustomLogger.php
new file mode 100644
index 0000000..c4bff3d
--- /dev/null
+++ b/tests/Logging/CustomLogger.php
@@ -0,0 +1,36 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Logging;
+
+use Psr\Log\AbstractLogger;
+
+class CustomLogger extends AbstractLogger
+{
+    public array $logs = [];
+
+    public function log($level, string|\Stringable $message, array $context = []): void
+    {
+        $this->logs[] = [
+            'level' => $level,
+            'message' => $message,
+            'context' => $context,
+        ];
+    }
+
+    public function hasLog(string $level, string $contains): bool
+    {
+        foreach ($this->logs as $log) {
+            if ($log['level'] === $level && str_contains($log['message'], $contains)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    public function clear(): void
+    {
+        $this->logs = [];
+    }
+}
diff --git a/tests/Logging/LogTest.php b/tests/Logging/LogTest.php
new file mode 100644
index 0000000..6847938
--- /dev/null
+++ b/tests/Logging/LogTest.php
@@ -0,0 +1,281 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Logging;
+
+use Icefox\DTO\Log;
+use Psr\Log\LogLevel;
+use Psr\Log\NullLogger;
+use Tests\Classes\PrimitiveData;
+use Tests\TestCase;
+
+describe('logger resolution', function () {
+
+    afterEach(function () {
+        config()->set('dto.log.logger', NullLogger::class);
+    });
+
+    it('uses NullLogger as fallback when logger config is null', function () {
+        config()->set('dto.log.logger', null);
+        $log = new Log();
+        expect($log->logger)->toBeInstanceOf(NullLogger::class);
+    });
+
+    it('uses NullLogger as fallback when logger config is invalid', function () {
+        config()->set('dto.log.logger', 'NonExistentLoggerClass');
+        $log = new Log();
+        expect($log->logger)->toBeInstanceOf(NullLogger::class);
+    });
+
+    it('instantiates logger from class name via Laravel container', function () {
+        config()->set('dto.log.logger', CustomLogger::class);
+        $log = new Log();
+        expect($log->logger)->toBeInstanceOf(CustomLogger::class);
+    });
+
+    it('uses logger object directly when provided', function () {
+        $customLogger = new CustomLogger();
+        config()->set('dto.log.logger', $customLogger);
+        $log = new Log();
+        expect($log->logger)->toBe($customLogger);
+    });
+
+    it('invokes callable to get logger instance', function () {
+        config()->set('dto.log.logger', function () {
+            return new CustomLogger();
+        });
+
+        $log = new Log();
+
+        expect($log->logger)->toBeInstanceOf(CustomLogger::class);
+    });
+});
+
+describe('log level configuration', function () {
+
+    beforeEach(function () {
+        $this->customLogger = new CustomLogger();
+        config()->set('dto.log.logger', $this->customLogger);
+    });
+
+    afterEach(function () {
+        config()->set('dto.log.logger', NullLogger::class);
+        config()->set('dto.log.rules', LogLevel::DEBUG);
+        config()->set('dto.log.input', LogLevel::DEBUG);
+        config()->set('dto.log.raw_input', LogLevel::DEBUG);
+        config()->set('dto.log.validation_errors', LogLevel::INFO);
+    });
+
+    it('logs rules at configured level', function () {
+        config()->set('dto.log.rules', LogLevel::INFO);
+
+        $log = new Log();
+        $log->rules(['field' => ['required']]);
+
+        expect($this->customLogger->hasLog(LogLevel::INFO, 'field'))->toBeTrue();
+    });
+
+    it('logs input at configured level', function () {
+        config()->set('dto.log.input', LogLevel::INFO);
+
+        $log = new Log();
+        $log->input(['field' => 'value']);
+
+        expect($this->customLogger->hasLog(LogLevel::INFO, 'value'))->toBeTrue();
+    });
+
+    it('logs raw input at configured level', function () {
+        config()->set('dto.log.raw_input', LogLevel::ERROR);
+
+        $log = new Log();
+        $log->inputRaw(['field' => 'raw_value']);
+
+        expect($this->customLogger->hasLog(LogLevel::ERROR, 'raw_value'))->toBeTrue();
+    });
+
+    it('logs validation errors at configured level', function () {
+        config()->set('dto.log.validation_errors', LogLevel::ERROR);
+
+        $log = new Log();
+        $log->validationErrors(['field' => ['The field is required.']]);
+
+        expect($this->customLogger->hasLog(LogLevel::ERROR, 'required'))->toBeTrue();
+    });
+
+    it('allows different log levels for each log type', function () {
+        config()->set('dto.log.rules', LogLevel::DEBUG);
+        config()->set('dto.log.input', LogLevel::INFO);
+        config()->set('dto.log.raw_input', LogLevel::INFO);
+
+        $log = new Log();
+
+        $log->rules(['rules_field' => ['required']]);
+        $log->input(['input_field' => 'value']);
+        $log->inputRaw(['raw_field' => 'raw_value']);
+
+        expect($this->customLogger->hasLog(LogLevel::DEBUG, 'rules_field'))->toBeTrue();
+        expect($this->customLogger->hasLog(LogLevel::INFO, 'input_field'))->toBeTrue();
+        expect($this->customLogger->hasLog(LogLevel::INFO, 'raw_field'))->toBeTrue();
+    });
+
+    it('defaults to DEBUG level when not configured', function () {
+        config()->set('dto.log.rules', null);
+        config()->set('dto.log.input', null);
+        config()->set('dto.log.raw_input', null);
+
+        $customLogger = new CustomLogger();
+        config()->set('dto.log.logger', $customLogger);
+
+        $log = new Log();
+
+        $log->rules(['field' => ['required']]);
+        $log->input(['field' => 'value']);
+        $log->inputRaw(['field' => 'raw_value']);
+
+        expect(count($customLogger->logs))->toBe(3);
+        expect($customLogger->logs[0]['level'])->toBe(LogLevel::DEBUG);
+        expect($customLogger->logs[1]['level'])->toBe(LogLevel::DEBUG);
+        expect($customLogger->logs[2]['level'])->toBe(LogLevel::DEBUG);
+    });
+});
+
+describe('integration with DataObject', function () {
+
+    beforeEach(function () {
+        $this->customLogger = new CustomLogger();
+        config()->set('dto.log.logger', $this->customLogger);
+        config()->set('dto.log.rules', LogLevel::DEBUG);
+        config()->set('dto.log.input', LogLevel::DEBUG);
+        config()->set('dto.log.raw_input', LogLevel::DEBUG);
+    });
+
+    afterEach(function () {
+        config()->set('dto.log.logger', NullLogger::class);
+    });
+
+    it('logs raw input during fromArray execution', function () {
+        PrimitiveData::fromArray([
+            'string' => 'test',
+            'int' => 42,
+            'float' => 3.14,
+            'bool' => true,
+        ]);
+
+        expect($this->customLogger->hasLog(LogLevel::DEBUG, 'raw_input'))->toBeFalse();
+        expect($this->customLogger->hasLog(LogLevel::DEBUG, 'string'))->toBeTrue();
+        expect($this->customLogger->hasLog(LogLevel::DEBUG, '42'))->toBeTrue();
+    });
+
+    it('logs rules during fromArray execution', function () {
+        PrimitiveData::fromArray([
+            'string' => 'test',
+            'int' => 42,
+            'float' => 3.14,
+            'bool' => true,
+        ]);
+
+        expect($this->customLogger->hasLog(LogLevel::DEBUG, 'required'))->toBeTrue();
+    });
+
+    it('logs processed input during fromArray execution', function () {
+        PrimitiveData::fromArray([
+            'string' => 'test',
+            'int' => 42,
+            'float' => 3.14,
+            'bool' => true,
+        ]);
+
+        expect($this->customLogger->hasLog(LogLevel::DEBUG, 'test'))->toBeTrue();
+    });
+
+    it('captures all three log types during successful fromArray', function () {
+        PrimitiveData::fromArray([
+            'string' => 'integration_test',
+            'int' => 123,
+            'float' => 9.99,
+            'bool' => false,
+        ]);
+
+        $rawInputLogged = false;
+        $rulesLogged = false;
+        $inputLogged = false;
+
+        foreach ($this->customLogger->logs as $log) {
+            if (str_contains($log['message'], 'string')) {
+                $rawInputLogged = true;
+            }
+            if (str_contains($log['message'], 'required')) {
+                $rulesLogged = true;
+            }
+            if (str_contains($log['message'], 'integration_test')) {
+                $inputLogged = true;
+            }
+        }
+
+        expect($rawInputLogged)->toBeTrue('Raw input should be logged');
+        expect($rulesLogged)->toBeTrue('Rules should be logged');
+        expect($inputLogged)->toBeTrue('Processed input should be logged');
+    });
+
+    it('logs even when validation fails', function () {
+        try {
+            PrimitiveData::fromArray([
+                'int' => 42,
+                'float' => 3.14,
+                'bool' => true,
+            ]);
+        } catch (\Illuminate\Validation\ValidationException $e) {
+            // Expected
+        }
+
+        expect($this->customLogger->hasLog(LogLevel::DEBUG, 'required'))->toBeTrue();
+        expect($this->customLogger->hasLog(LogLevel::DEBUG, '42'))->toBeTrue();
+    });
+
+    it('logs validation errors when validation fails', function () {
+        config()->set('dto.log.validation_errors', LogLevel::ERROR);
+
+        try {
+            PrimitiveData::fromArray([
+                'int' => 42,
+                'float' => 3.14,
+                'bool' => true,
+            ]);
+        } catch (\Illuminate\Validation\ValidationException $e) {
+            // Expected
+        }
+
+        expect($this->customLogger->hasLog(LogLevel::ERROR, 'string'))->toBeTrue();
+        expect($this->customLogger->hasLog(LogLevel::ERROR, 'required'))->toBeTrue();
+    });
+});
+
+describe('logging with NullLogger', function () {
+
+    it('does not throw when logging with NullLogger', function () {
+        config()->set('dto.log.logger', NullLogger::class);
+
+        $log = new Log();
+
+        expect(function () use ($log) {
+            $log->rules(['field' => ['required']]);
+            $log->input(['field' => 'value']);
+            $log->inputRaw(['field' => 'raw_value']);
+        })->not->toThrow(\Throwable::class);
+    });
+
+    it('does not affect DataObject behavior when using NullLogger', function () {
+        config()->set('dto.log.logger', NullLogger::class);
+
+        $object = PrimitiveData::fromArray([
+            'string' => 'test',
+            'int' => 42,
+            'float' => 3.14,
+            'bool' => true,
+        ]);
+
+        expect($object)->toBeInstanceOf(PrimitiveData::class);
+        expect($object->string)->toBe('test');
+    });
+});