diff --git a/README.md b/README.md
index 29cfe33..8b05664 100644
--- a/README.md
+++ b/README.md
@@ -238,6 +238,7 @@ shortcuts: {
 
 **Inputs**
 
+<<<<<<< HEAD
 | Input                 | Type       | Default | Description                                                                                                   |
 | --------------------- | ---------- | ------- | ------------------------------------------------------------------------------------------------------------- |
 | selectedItems         | Array<any> | /       | Collection of items that are currently selected                                                               |
@@ -247,7 +248,8 @@ shortcuts: {
 | disableDrag           | Boolean    | `false` | Disable selection by dragging with the mouse. May be useful for mobile.                                       |
 | selectMode            | Boolean    | `false` | If set to `true`, a _toggle_ mode is activated similar to the `toggleSingleItem` shortcut. Useful for mobile. |
 | custom                | Boolean    | `false` | If set to `true`, all default styles for selected items will not be applied.                                  |
-| selectWithShortcut    | Boolean    | `false` | If set to `true`, items can only be selected when single clicking and applying a keyboard shortcut            |
+| selectWithShortcut    | Boolean    | `false` | If set to `true`, items can only be selected when single clicking and applying a keyboard shortcut            |          |
+| additive           | Boolean    | `false` | If set to `true`, will add items to selection the same way as holding the `shift` key.                        |
 
 Here's an example of all inputs in action:
 
@@ -259,7 +261,8 @@ Here's an example of all inputs in action:
   [disableDrag]="true"
   [selectMode]="true"
   [custom]="true"
-  [selectWithShortcut]="false">
+  [selectWithShortcut]="false"
+  [additive]="true">
   ...
 </dts-select-container>
 ```
diff --git a/cypress/integration/dragging.spec.ts b/cypress/integration/dragging.spec.ts
index 70f1b45..c4bc6cd 100644
--- a/cypress/integration/dragging.spec.ts
+++ b/cypress/integration/dragging.spec.ts
@@ -4,6 +4,7 @@ import {
   disableSelection,
   disableSelectOnDrag,
   enableSelectMode,
+  enableAdditive,
   getDesktopExample,
   shouldBeInvisible,
   shouldBeVisible,
@@ -372,6 +373,36 @@ describe('Dragging', () => {
     });
   });
 
+  describe('Additive', () => {
+    beforeEach(() => {
+      enableAdditive();
+    });
+
+    it('should extend selection after mouseup', () => {
+      getDesktopExample().within(() => {
+        cy.getSelectItem(0)
+          .dispatch('mousedown', { button: 0 })
+          .getSelectItem(5)
+          .dispatch('mousemove')
+          .dispatch('mouseup')
+          .shouldSelect([1, 2, 5, 6])
+          .getSelectItem(2)
+          .dispatch('mousedown', { button: 0 })
+          .getSelectItem(7)
+          .as('end')
+          .dispatch('mousemove')
+          .shouldSelect([1, 2, 5, 6])
+          .get(`.${SELECTED_CLASS}`)
+          .should('have.length', 8)
+          .get('@end')
+          .dispatch('mouseup')
+          .shouldSelect([1, 2, 3, 4, 5, 6, 7, 8])
+          .get(`.${SELECTED_CLASS}`)
+          .should('have.length', 8);
+      });
+    });
+  });
+
   describe('Shortcuts', () => {
     it('should toggle single items', () => {
       getDesktopExample().within(() => {
diff --git a/cypress/support/utils.ts b/cypress/support/utils.ts
index 1b7ee73..a0e6c5b 100644
--- a/cypress/support/utils.ts
+++ b/cypress/support/utils.ts
@@ -68,6 +68,10 @@ export const enableSelectWithShortcut = () => {
   return cy.get('[data-cy="selectWithShortcut"]').click();
 };
 
+export const enableAdditive = () => {
+  return cy.get('[data-cy="additive"]').click();
+};
+
 export const selectAll = () => {
   return getSelectAllButton().click();
 };
diff --git a/projects/ngx-drag-to-select/src/lib/select-container.component.ts b/projects/ngx-drag-to-select/src/lib/select-container.component.ts
index 7f8ee81..64d7f50 100644
--- a/projects/ngx-drag-to-select/src/lib/select-container.component.ts
+++ b/projects/ngx-drag-to-select/src/lib/select-container.component.ts
@@ -103,6 +103,7 @@ export class SelectContainerComponent implements AfterViewInit, OnDestroy, After
   @Input() disableRangeSelection = false;
   @Input() selectMode = false;
   @Input() selectWithShortcut = false;
+  @Input() additive = false;
 
   @Input()
   @HostBinding('class.dts-custom')
@@ -466,7 +467,7 @@ export class SelectContainerComponent implements AfterViewInit, OnDestroy, After
       const itemRect = item.getBoundingClientRect();
       const withinBoundingBox = inBoundingBox(mousePoint, itemRect);
 
-      if (this.shortcuts.extendedSelectionShortcut(event) && this.disableRangeSelection) {
+      if (this.shortcuts.extendedSelectionShortcut(event) && this.disableRangeSelection || this.additive) {
         return;
       }
 
@@ -540,7 +541,7 @@ export class SelectContainerComponent implements AfterViewInit, OnDestroy, After
   }
 
   private _isExtendedSelection(event: Event) {
-    return this.shortcuts.extendedSelectionShortcut(event) && this.selectOnDrag;
+    return (this.shortcuts.extendedSelectionShortcut(event) || this.additive) && this.selectOnDrag;
   }
 
   private _normalSelectionMode(selectBox: BoundingBox, item: SelectItemDirective, event: Event) {
@@ -567,7 +568,10 @@ export class SelectContainerComponent implements AfterViewInit, OnDestroy, After
       (inSelection && item.selected && this.shortcuts.removeFromSelection(event) && !this._tmpItems.has(item));
 
     const shouldRemove =
-      (!inSelection && item.selected && this.shortcuts.addToSelection(event) && this._tmpItems.has(item)) ||
+      (!inSelection &&
+        item.selected &&
+        (this.shortcuts.addToSelection(event) || this.additive) &&
+        this._tmpItems.has(item)) ||
       (!inSelection && !item.selected && this.shortcuts.removeFromSelection(event) && this._tmpItems.has(item));
 
     if (shoudlAdd) {
@@ -575,7 +579,7 @@ export class SelectContainerComponent implements AfterViewInit, OnDestroy, After
 
       const action = this.shortcuts.removeFromSelection(event)
         ? Action.Delete
-        : this.shortcuts.addToSelection(event)
+        : this.shortcuts.addToSelection(event) || this.additive
         ? Action.Add
         : Action.None;
 
diff --git a/src/app/app.component.html b/src/app/app.component.html
index 70c95fe..9f46247 100644
--- a/src/app/app.component.html
+++ b/src/app/app.component.html
@@ -26,6 +26,7 @@ <h3>
     >
     <mat-checkbox data-cy="selectMode" [(ngModel)]="selectMode">Select Mode</mat-checkbox>
     <mat-checkbox data-cy="selectWithShortcut" [(ngModel)]="selectWithShortcut">Select with Shortcut</mat-checkbox>
+    <mat-checkbox data-cy="additive" [(ngModel)]="additive">Additive</mat-checkbox>
 
     <div class="action-buttons">
       <button data-cy="selectAll" mat-raised-button (click)="selectContainer.selectAll()">Select All</button>
@@ -44,6 +45,7 @@ <h3>
         [disableRangeSelection]="disableRangeSelection"
         [selectOnDrag]="selectOnDrag"
         [selectWithShortcut]="selectWithShortcut"
+        [additive]="additive"
       >
         <mat-grid-list cols="4" rowHeight="200px" gutterSize="20px">
           <mat-grid-tile [dtsSelectItem]="document" *ngFor="let document of documents">
diff --git a/src/app/app.component.ts b/src/app/app.component.ts
index 1a4ee2f..9b85740 100644
--- a/src/app/app.component.ts
+++ b/src/app/app.component.ts
@@ -19,6 +19,7 @@ export class AppComponent implements OnInit {
   disableRangeSelection = false;
   isDesktop = false;
   selectWithShortcut = false;
+  additive = false;
 
   constructor(
     private titleService: Title,