diff --git a/dangerzone/document.py b/dangerzone/document.py
index d1e311c..415b92d 100644
--- a/dangerzone/document.py
+++ b/dangerzone/document.py
@@ -30,12 +30,18 @@ class Document:
     STATE_SAFE = enum.auto()
     STATE_FAILED = enum.auto()
 
-    def __init__(self, input_filename: str = None, output_filename: str = None) -> None:
+    def __init__(
+        self,
+        input_filename: str = None,
+        output_filename: str = None,
+        suffix: str = SAFE_EXTENSION,
+    ) -> None:
         # NOTE: See https://github.com/freedomofpress/dangerzone/pull/216#discussion_r1015449418
         self.id = secrets.token_urlsafe(6)[0:6]
 
         self._input_filename: Optional[str] = None
         self._output_filename: Optional[str] = None
+        self._suffix = suffix
 
         if input_filename:
             self.input_filename = input_filename
@@ -97,13 +103,35 @@ class Document:
         self.validate_output_filename(filename)
         self._output_filename = filename
 
+    @property
+    def suffix(self) -> str:
+        return self._suffix
+
+    @suffix.setter
+    def suffix(self, suf: str) -> None:
+        self._suffix = suf
+
     @property
     def default_output_filename(self) -> str:
-        return f"{os.path.splitext(self.input_filename)[0]}{SAFE_EXTENSION}"
+        return f"{os.path.splitext(self.input_filename)[0]}{self.suffix}"
 
     def announce_id(self) -> None:
         log.info(f"Assigning ID '{self.id}' to doc '{self.input_filename}'")
 
+    def set_output_dir(self, path: str) -> None:
+        # keep the same name
+        old_filename = os.path.basename(self.output_filename)
+
+        new_path = os.path.abspath(path)
+        if not os.path.exists(new_path):
+            raise errors.NonExistantOutputDirException()
+        if not os.path.isdir(new_path):
+            raise errors.OutputDirIsNotDirException()
+        if not os.access(new_path, os.W_OK):
+            raise errors.UnwriteableOutputDirException()
+
+        self._output_filename = os.path.join(new_path, old_filename)
+
     def is_unconverted(self) -> bool:
         return self.state is Document.STATE_UNCONVERTED
 
diff --git a/dangerzone/errors.py b/dangerzone/errors.py
index 1e6811a..e012235 100644
--- a/dangerzone/errors.py
+++ b/dangerzone/errors.py
@@ -57,6 +57,20 @@ class NotSetOutputFilenameException(DocumentFilenameException):
         super().__init__("Output filename has not been set yet.")
 
 
+class NonExistantOutputDirException(DocumentFilenameException):
+    """Exception for when the output dir does not exist."""
+
+    def __init__(self) -> None:
+        super().__init__("Output directory does not exist")
+
+
+class OutputDirIsNotDirException(DocumentFilenameException):
+    """Exception for when the specified output dir is not actually a dir."""
+
+    def __init__(self) -> None:
+        super().__init__("Specified output directory is actually not a directory")
+
+
 def handle_document_errors(func: F) -> F:
     """Log document-related errors and exit gracefully."""
 
diff --git a/tests/test_document.py b/tests/test_document.py
index 3b0bdba..264bcdd 100644
--- a/tests/test_document.py
+++ b/tests/test_document.py
@@ -1,12 +1,13 @@
 import os
 import platform
+import stat
 import tempfile
 from pathlib import Path
 
 import pytest
 
 from dangerzone import errors
-from dangerzone.document import Document
+from dangerzone.document import SAFE_EXTENSION, Document
 
 from . import sample_doc, unreadable_pdf
 
@@ -68,7 +69,7 @@ def test_output_file_none() -> None:
 
 
 def test_output_file_not_pdf(tmp_path: Path) -> None:
-    docx_file = str(tmp_path.joinpath("document.docx"))
+    docx_file = str(tmp_path / "document.docx")
     d = Document()
 
     with pytest.raises(errors.NonPDFOutputFileException) as e:
@@ -77,7 +78,43 @@ def test_output_file_not_pdf(tmp_path: Path) -> None:
     assert not os.path.exists(docx_file)
 
 
-def test_is_unconverted_by_default(sample_doc: None) -> None:
+def test_set_output_dir(sample_doc: str, tmp_path: Path) -> None:
+    d = Document(sample_doc)
+    d.set_output_dir(str(tmp_path))
+    assert os.path.dirname(d.output_filename) == str(tmp_path)
+
+
+def test_set_output_dir_non_existant(sample_doc: str, tmp_path: Path) -> None:
+    non_existant_path = str(tmp_path / "fake-dir")
+    d = Document(sample_doc)
+    with pytest.raises(errors.NonExistantOutputDirException):
+        d.set_output_dir(non_existant_path)
+
+
+def test_set_output_dir_is_file(sample_doc: str, tmp_path: Path) -> None:
+    # create a file
+    file_path = str(tmp_path / "file")
+    with open(file_path, "w"):
+        pass
+
+    d = Document(sample_doc)
+    with pytest.raises(errors.OutputDirIsNotDirException):
+        d.set_output_dir(file_path)
+
+
+def test_default_output_filename(sample_doc: str) -> None:
+    d = Document(sample_doc)
+    assert d.output_filename.endswith(SAFE_EXTENSION)
+
+
+def test_set_output_filename_suffix(sample_doc: str) -> None:
+    d = Document(sample_doc)
+    safe_extension = "-trusted.pdf"
+    d.suffix = safe_extension
+    assert d.output_filename.endswith(safe_extension)
+
+
+def test_is_unconverted_by_default(sample_doc: str) -> None:
     d = Document(sample_doc)
     assert d.is_unconverted()