diff --git a/routes/confirm_save.py b/routes/confirm_save.py
index f72cb2d..564cd67 100644
--- a/routes/confirm_save.py
+++ b/routes/confirm_save.py
@@ -11,14 +11,14 @@ def confirm_save():
     # Check if assets data is present in the request
     if 'assets' not in request.form:
         flash("No assets data found in the request.", "error")
-        return redirect(url_for('uploadcsv.upload_file'))
+        return redirect(url_for('uploadcsv.import_from_csv'))
 
     try:
         # Parse the JSON data from the form
         edited_assets = json.loads(request.form['assets'])
     except json.JSONDecodeError:
         flash("Invalid JSON data in the request.", "error")
-        return redirect(url_for('uploadcsv.upload_file'))
+        return redirect(url_for('uploadcsv.import_from_csv'))
 
     # Validate each asset
     errors = []
@@ -31,23 +31,36 @@ def confirm_save():
         # If there are validation errors, flash them and redirect back to the preview page
         for error in errors:
             flash(error, "error")
-        return redirect(url_for('uploadcsv.upload_file'))
+        return redirect(url_for('uploadcsv.import_from_csv'))
 
     # Save validated assets to the database
     for asset_data in edited_assets:
-        asset = Asset(**{
-            attrib.attrib_name: asset_data[attrib.attrib_name]
-            for attrib in item_attributes
-        })
-        db.session.add(asset)
+        primary_attrib = next((attrib for attrib in item_attributes if attrib.primary), None)
+        if not primary_attrib:
+            flash("Primary attribute not defined in configuration.", "error")
+            return redirect(url_for('uploadcsv.import_from_csv'))
+
+        primary_value = asset_data[primary_attrib.attrib_name]
+        asset = Asset.query.filter_by(**{primary_attrib.attrib_name: primary_value}).first()
+
+        if asset:
+            # Update existing asset
+            for attrib in item_attributes:
+                setattr(asset, attrib.attrib_name, asset_data[attrib.attrib_name])
+        else:
+            # Add new asset
+            asset = Asset(**asset_data)
+            db.session.add(asset)
 
     try:
         db.session.commit()
     except Exception as e:
         db.session.rollback()
         flash(f"Error saving data to the database: {str(e)}", "error")
-        return redirect(url_for('uploadcsv.upload_file'))
+        return redirect(url_for('uploadcsv.import_from_csv'))
 
     # Clear session data after successful insertion
-    session.pop('assets', None)
+    session.pop('new_entries', None)
+    session.pop('existing_entries', None)
+    session.pop('invalid_entries', None)
     return redirect('/viewall')
\ No newline at end of file
diff --git a/routes/upload.py b/routes/upload.py
index 222eede..e919a82 100644
--- a/routes/upload.py
+++ b/routes/upload.py
@@ -6,14 +6,56 @@ from config import item_attributes
 
 upload_bp = Blueprint('uploadcsv', __name__)
 
-@upload_bp.route('/uploadcsv', methods=['GET', 'POST'])
-def upload_file():
-    # Check if primary attribute is defined
+def _process_csv_file(file, mode):
+    """
+    Helper function to process CSV file and separate entries based on mode.
+    mode: 'import' or 'edit'
+    """
+    # Extract CSV data
+    csvdata = get_csv_data(file)
+
+    # Validate each row of data
+    errors = []
+    for i, row in enumerate(csvdata, start=1):
+        error = validate_values(row)
+        if error:
+            errors.append(f"Row {i}: {error}")
+
+    if errors:
+        return None, errors
+
+    # Separate entries based on mode
     primary_attrib = next((attrib for attrib in item_attributes if attrib.primary), None)
     if not primary_attrib:
-        flash("Primary attribute not defined in configuration.", "error")
-        return redirect(request.url)
+        return None, ["Primary attribute not defined in configuration."]
 
+    new_entries = []
+    existing_entries = []
+    invalid_entries = []
+
+    for row in csvdata:
+        primary_value = row[primary_attrib.attrib_name]
+        asset_exists = Asset.query.filter_by(**{primary_attrib.attrib_name: primary_value}).first()
+
+        if mode == 'import':
+            if asset_exists:
+                invalid_entries.append(row)  # Existing entries are invalid for import
+            else:
+                new_entries.append(row)
+        elif mode == 'edit':
+            if asset_exists:
+                existing_entries.append(row)  # Existing entries are valid for edit
+            else:
+                invalid_entries.append(row)  # Non-existing entries are invalid for edit
+
+    return {
+        'new_entries': new_entries,
+        'existing_entries': existing_entries,
+        'invalid_entries': invalid_entries
+    }, None
+
+@upload_bp.route('/import_from_csv', methods=['GET', 'POST'])
+def import_from_csv():
     if request.method == 'POST':
         # Check if a file was uploaded
         if 'file' not in request.files:
@@ -27,48 +69,61 @@ def upload_file():
             flash("Please upload a valid CSV file.", "error")
             return redirect(request.url)
 
-        try:
-            # Extract CSV data
-            csvdata = get_csv_data(file)
-        except Exception as e:
-            flash(f"Error reading CSV file: {str(e)}", "error")
-            return redirect(request.url)
-
-        # Validate each row of data
-        errors = []
-        for i, row in enumerate(csvdata, start=1):
-            error = validate_values(row)
-            if error:
-                errors.append(f"Row {i}: {error}")
-
+        # Process the CSV file
+        result, errors = _process_csv_file(file, mode='import')
         if errors:
-            # Flash all errors and redirect back to the upload page
             for error in errors:
                 flash(error, "error")
             return redirect(request.url)
 
-        # Separate new and existing assets
-        new_assets = []
-        existing_assets = []
-        for row in csvdata:
-            primary_value = row[primary_attrib.attrib_name]
-            asset_exists = Asset.query.filter_by(**{primary_attrib.attrib_name: primary_value}).first()
-            if asset_exists:
-                existing_assets.append(row)
-            else:
-                new_assets.append(row)
+        # Store entries in session for further processing
+        session['new_entries'] = result['new_entries']
+        session['invalid_entries'] = result['invalid_entries']
 
-        # Store new assets in session for further processing
-        session['new_assets'] = new_assets
-        session['existing_assets'] = existing_assets
-
-        # Redirect to preview page with the CSV data
+        # Redirect to preview page
         return render_template(
             'csv_preview.html',
-            new_assets=new_assets,
-            existing_assets=existing_assets,
+            new_entries=result['new_entries'],
+            invalid_entries=result['invalid_entries'],
             item_attributes=item_attributes
         )
 
     # Render the upload page for GET requests
-    return render_template('upload.html')
\ No newline at end of file
+    return render_template('upload.html', mode="addnew")
+
+@upload_bp.route('/edit_using_csv', methods=['GET', 'POST'])
+def edit_using_csv():
+    if request.method == 'POST':
+        # Check if a file was uploaded
+        if 'file' not in request.files:
+            flash("No file uploaded.", "error")
+            return redirect(request.url)
+
+        file = request.files['file']
+
+        # Check if the file is a CSV
+        if file.filename == '' or not file.filename.endswith('.csv'):
+            flash("Please upload a valid CSV file.", "error")
+            return redirect(request.url)
+
+        # Process the CSV file
+        result, errors = _process_csv_file(file, mode='edit')
+        if errors:
+            for error in errors:
+                flash(error, "error")
+            return redirect(request.url)
+
+        # Store entries in session for further processing
+        session['existing_entries'] = result['existing_entries']
+        session['invalid_entries'] = result['invalid_entries']
+
+        # Redirect to preview page
+        return render_template(
+            'csv_preview.html',
+            existing_entries=result['existing_entries'],
+            invalid_entries=result['invalid_entries'],
+            item_attributes=item_attributes
+        )
+
+    # Render the upload page for GET requests
+    return render_template('upload.html', mode="update")
\ No newline at end of file
diff --git a/static/edited_csv.js b/static/edited_csv.js
index cf26c0a..a0327b8 100644
--- a/static/edited_csv.js
+++ b/static/edited_csv.js
@@ -3,8 +3,8 @@ function collectEditedData(event) {
     event.preventDefault();
 
     // Extract headers (attribute names) from the table
-    const headers = [...document.querySelectorAll('.table-new-assets thead th')].map(th => th.dataset.attrib);
-    const rows = document.querySelectorAll('.table-new-assets tbody tr');
+    const headers = [...document.querySelectorAll('.table-valid-entries thead th')].map(th => th.dataset.attrib);
+    const rows = document.querySelectorAll('.table-valid-entries tbody tr');
     const assets = [];
 
     // Iterate through rows and collect data
diff --git a/templates/csv_preview.html b/templates/csv_preview.html
index e6abc22..a5e64f6 100644
--- a/templates/csv_preview.html
+++ b/templates/csv_preview.html
@@ -23,27 +23,28 @@
         {% endif %}
     {% endwith %}
 
-    <!-- Render tables for new and existing assets -->
-    {% for table_name, assets, editable, table_class in [
-        ('New Assets', new_assets, true, 'table-new-assets'),
-        ('Existing Assets', existing_assets, false, 'table-existing-assets')
+    <!-- Render tables for new, existing, and invalid entries -->
+    {% for table_name, entries, editable, tableclass in [
+        ('New Entries', new_entries, true, 'table-valid-entries'),
+        ('Existing Entries', existing_entries, true, 'table-valid-entries'),
+        ('Invalid Entries', invalid_entries, false, 'table-invalid-entries')
     ] %}
-        {% if assets %}
+        {% if entries %}
             <h2>{{ table_name }}</h2>
-            <table border="1" class="{{ table_class }}">
+            <table border="1" class="{{ tableclass }}">
                 <thead>
                     <tr>
                         {% for attrib in item_attributes %}
-                            <th data-attrib="{{ attrib.attrib_name }}">{{ attrib.display_name }}</th>
+                            <th>{{ attrib.display_name }}</th>
                         {% endfor %}
                     </tr>
                 </thead>
                 <tbody>
-                    {% for asset in assets %}
+                    {% for entry in entries %}
                         <tr>
                             {% for attrib in item_attributes %}
                                 <td {% if editable %}contenteditable="true"{% endif %}>
-                                    {{ asset[attrib.attrib_name] }}
+                                    {{ entry[attrib.attrib_name] }}
                                 </td>
                             {% endfor %}
                         </tr>
@@ -54,7 +55,7 @@
     {% endfor %}
 
     <!-- Form button to confirm and save data -->
-    {% if new_assets %}
+    {% if new_entries or existing_entries %}
     <form action="/confirm_save" method="POST" onsubmit="return collectEditedData(event)">
         <button type="submit">Confirm and Save to Database</button>
     </form>
diff --git a/templates/upload.html b/templates/upload.html
index 544f344..34396c2 100644
--- a/templates/upload.html
+++ b/templates/upload.html
@@ -23,7 +23,13 @@
     {% endwith %}
 
     <!-- Upload form -->
-    <form action="/uploadcsv" method="POST" enctype="multipart/form-data">
+    <form method="POST" enctype="multipart/form-data"
+        {% if mode == "addnew" %}
+            action="/import_from_csv"
+        {% elif mode == "addnew" %}
+            action="/edit_using_csv"
+        {% endif %}
+    >
         <label for="file">Choose a CSV file:</label>
         <input type="file" id="file" name="file" accept=".csv" required>
         <br><br>
diff --git a/templates/viewList.html b/templates/viewList.html
index 48ca566..fef8e1b 100644
--- a/templates/viewList.html
+++ b/templates/viewList.html
@@ -40,9 +40,12 @@
     <form action="/create" method="get">
         <button type="submit">Add new Item</button>
     </form>
-    <form action="/uploadcsv" method="get">
+    <form action="/import_from_csv" method="get">
         <button type="submit">Import from CSV</button>
     </form>
+    <form action="/edit_using_csv" method="get">
+        <button type="submit">Edit using CSV</button>
+    </form>
     <form action="/export_csv" method="POST">
         <button type="submit">Export Data</button>
     </form>