diff --git a/src/storage/database.py b/src/storage/database.py
new file mode 100644
index 0000000..163a834
--- /dev/null
+++ b/src/storage/database.py
@@ -0,0 +1,325 @@
+"""Database management for DevTrace."""
+
+import sqlite3
+from datetime import datetime
+from pathlib import Path
+from typing import Optional, List, Dict, Any
+from dataclasses import dataclass
+
+from .models import (
+    Session,
+    FileEvent,
+    CommandEvent,
+    GitEvent,
+    EventType
+)
+
+
+class Database:
+    """Manages SQLite database operations for DevTrace."""
+
+    def __init__(self, db_path: Path):
+        self.db_path = db_path
+        self._connection: Optional[sqlite3.Connection] = None
+
+    def _get_connection(self) -> sqlite3.Connection:
+        """Get database connection."""
+        if self._connection is None:
+            self._connection = sqlite3.connect(str(self.db_path))
+            self._connection.row_factory = sqlite3.Row
+            self._connection.execute("PRAGMA foreign_keys = ON")
+        return self._connection
+
+    def close(self) -> None:
+        """Close database connection."""
+        if self._connection:
+            self._connection.close()
+            self._connection = None
+
+    def initialize(self) -> None:
+        """Initialize database schema."""
+        conn = self._get_connection()
+
+        conn.executescript("""
+            CREATE TABLE IF NOT EXISTS sessions (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                name TEXT NOT NULL,
+                directory TEXT NOT NULL,
+                start_time TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+                end_time TIMESTAMP,
+                notes TEXT
+            );
+
+            CREATE TABLE IF NOT EXISTS file_events (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                session_id INTEGER NOT NULL,
+                event_type TEXT NOT NULL,
+                file_path TEXT NOT NULL,
+                timestamp TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+                details TEXT,
+                content_hash TEXT,
+                FOREIGN KEY (session_id) REFERENCES sessions(id)
+            );
+
+            CREATE TABLE IF NOT EXISTS command_events (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                session_id INTEGER NOT NULL,
+                command TEXT NOT NULL,
+                timestamp TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+                exit_code INTEGER,
+                working_directory TEXT,
+                details TEXT,
+                FOREIGN KEY (session_id) REFERENCES sessions(id)
+            );
+
+            CREATE TABLE IF NOT EXISTS git_events (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                session_id INTEGER NOT NULL,
+                operation TEXT NOT NULL,
+                branch TEXT,
+                commit_hash TEXT,
+                timestamp TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+                details TEXT,
+                diff TEXT,
+                FOREIGN KEY (session_id) REFERENCES sessions(id)
+            );
+
+            CREATE INDEX IF NOT EXISTS idx_file_events_session ON file_events(session_id);
+            CREATE INDEX IF NOT EXISTS idx_command_events_session ON command_events(session_id);
+            CREATE INDEX IF NOT EXISTS idx_git_events_session ON git_events(session_id);
+        """)
+
+        conn.commit()
+
+    def create_session(
+        self,
+        name: str,
+        directory: str,
+        notes: Optional[str] = None
+    ) -> Session:
+        """Create a new session."""
+        conn = self._get_connection()
+        cursor = conn.execute(
+            """
+            INSERT INTO sessions (name, directory, notes)
+            VALUES (?, ?, ?)
+            """,
+            (name, directory, notes)
+        )
+        conn.commit()
+
+        return Session(
+            id=cursor.lastrowid,
+            name=name,
+            directory=directory,
+            start_time=datetime.now(),
+            end_time=None,
+            notes=notes
+        )
+
+    def get_session(self, session_id: int) -> Optional[Session]:
+        """Get a session by ID."""
+        conn = self._get_connection()
+        row = conn.execute(
+            "SELECT * FROM sessions WHERE id = ?",
+            (session_id,)
+        ).fetchone()
+
+        if row is None:
+            return None
+
+        return Session(
+            id=row["id"],
+            name=row["name"],
+            directory=row["directory"],
+            start_time=datetime.fromisoformat(row["start_time"]) if row["start_time"] else None,
+            end_time=datetime.fromisoformat(row["end_time"]) if row["end_time"] else None,
+            notes=row["notes"]
+        )
+
+    def get_all_sessions(self) -> List[Session]:
+        """Get all sessions."""
+        conn = self._get_connection()
+        rows = conn.execute("SELECT * FROM sessions ORDER BY start_time DESC").fetchall()
+
+        return [
+            Session(
+                id=row["id"],
+                name=row["name"],
+                directory=row["directory"],
+                start_time=datetime.fromisoformat(row["start_time"]) if row["start_time"] else None,
+                end_time=datetime.fromisoformat(row["end_time"]) if row["end_time"] else None,
+                notes=row["notes"]
+            )
+            for row in rows
+        ]
+
+    def end_session(self, session_id: int) -> bool:
+        """End a session."""
+        conn = self._get_connection()
+        cursor = conn.execute(
+            "UPDATE sessions SET end_time = CURRENT_TIMESTAMP WHERE id = ?",
+            (session_id,)
+        )
+        conn.commit()
+        return cursor.rowcount > 0
+
+    def add_file_event(
+        self,
+        session_id: int,
+        event_type: str,
+        file_path: str,
+        details: Optional[str] = None,
+        content_hash: Optional[str] = None
+    ) -> int:
+        """Add a file event."""
+        conn = self._get_connection()
+        cursor = conn.execute(
+            """
+            INSERT INTO file_events (session_id, event_type, file_path, details, content_hash)
+            VALUES (?, ?, ?, ?, ?)
+            """,
+            (session_id, event_type, file_path, details, content_hash)
+        )
+        conn.commit()
+        return cursor.lastrowid
+
+    def get_file_events(self, session_id: int, limit: int = 100) -> List[FileEvent]:
+        """Get file events for a session."""
+        conn = self._get_connection()
+        rows = conn.execute(
+            "SELECT * FROM file_events WHERE session_id = ? ORDER BY timestamp DESC LIMIT ?",
+            (session_id, limit)
+        ).fetchall()
+
+        return [
+            FileEvent(
+                id=row["id"],
+                session_id=row["session_id"],
+                event_type=row["event_type"],
+                file_path=row["file_path"],
+                timestamp=datetime.fromisoformat(row["timestamp"]) if row["timestamp"] else None,
+                details=row["details"],
+                content_hash=row["content_hash"]
+            )
+            for row in rows
+        ]
+
+    def add_command_event(
+        self,
+        session_id: int,
+        command: str,
+        exit_code: Optional[int] = None,
+        working_directory: Optional[str] = None,
+        details: Optional[str] = None
+    ) -> int:
+        """Add a command event."""
+        conn = self._get_connection()
+        cursor = conn.execute(
+            """
+            INSERT INTO command_events (session_id, command, exit_code, working_directory, details)
+            VALUES (?, ?, ?, ?, ?)
+            """,
+            (session_id, command, exit_code, working_directory, details)
+        )
+        conn.commit()
+        return cursor.lastrowid
+
+    def get_command_events(self, session_id: int, limit: int = 100) -> List[CommandEvent]:
+        """Get command events for a session."""
+        conn = self._get_connection()
+        rows = conn.execute(
+            "SELECT * FROM command_events WHERE session_id = ? ORDER BY timestamp DESC LIMIT ?",
+            (session_id, limit)
+        ).fetchall()
+
+        return [
+            CommandEvent(
+                id=row["id"],
+                session_id=row["session_id"],
+                command=row["command"],
+                timestamp=datetime.fromisoformat(row["timestamp"]) if row["timestamp"] else None,
+                exit_code=row["exit_code"],
+                working_directory=row["working_directory"],
+                details=row["details"]
+            )
+            for row in rows
+        ]
+
+    def add_git_event(
+        self,
+        session_id: int,
+        operation: str,
+        branch: Optional[str] = None,
+        commit_hash: Optional[str] = None,
+        details: Optional[str] = None,
+        diff: Optional[str] = None
+    ) -> int:
+        """Add a git event."""
+        conn = self._get_connection()
+        cursor = conn.execute(
+            """
+            INSERT INTO git_events (session_id, operation, branch, commit_hash, details, diff)
+            VALUES (?, ?, ?, ?, ?, ?)
+            """,
+            (session_id, operation, branch, commit_hash, details, diff)
+        )
+        conn.commit()
+        return cursor.lastrowid
+
+    def get_git_events(self, session_id: int, limit: int = 100) -> List[GitEvent]:
+        """Get git events for a session."""
+        conn = self._get_connection()
+        rows = conn.execute(
+            "SELECT * FROM git_events WHERE session_id = ? ORDER BY timestamp DESC LIMIT ?",
+            (session_id, limit)
+        ).fetchall()
+
+        return [
+            GitEvent(
+                id=row["id"],
+                session_id=row["session_id"],
+                operation=row["operation"],
+                branch=row["branch"],
+                commit_hash=row["commit_hash"],
+                timestamp=datetime.fromisoformat(row["timestamp"]) if row["timestamp"] else None,
+                details=row["details"],
+                diff=row["diff"]
+            )
+            for row in rows
+        ]
+
+    def get_session_events(
+        self,
+        session_id: int,
+        limit: int = 100
+    ) -> List[FileEvent | CommandEvent | GitEvent]:
+        """Get all events for a session."""
+        events: List[FileEvent | CommandEvent | GitEvent] = []
+        events.extend(self.get_file_events(session_id, limit))
+        events.extend(self.get_command_events(session_id, limit))
+        events.extend(self.get_git_events(session_id, limit))
+        events.sort(key=lambda e: e.timestamp or datetime.min, reverse=True)
+        return events[:limit]
+
+    def get_stats(self) -> Dict[str, Any]:
+        """Get database statistics."""
+        conn = self._get_connection()
+
+        session_count = conn.execute("SELECT COUNT(*) FROM sessions").fetchone()[0]
+        active_sessions = conn.execute(
+            "SELECT COUNT(*) FROM sessions WHERE end_time IS NULL"
+        ).fetchone()[0]
+        file_event_count = conn.execute("SELECT COUNT(*) FROM file_events").fetchone()[0]
+        command_event_count = conn.execute("SELECT COUNT(*) FROM command_events").fetchone()[0]
+        git_event_count = conn.execute("SELECT COUNT(*) FROM git_events").fetchone()[0]
+
+        return {
+            "total_sessions": session_count,
+            "active_sessions": active_sessions,
+            "file_events": file_event_count,
+            "command_events": command_event_count,
+            "git_events": git_event_count,
+            "total_events": file_event_count + command_event_count + git_event_count,
+            "db_path": str(self.db_path)
+        }