diff --git a/CHANGELOG.md b/CHANGELOG.md
index a093d10..138823c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,9 +4,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [0.7.0] - 2021-02-12
+## [Unreleased]
 ### Added
 * Single key prompts for key-values - `chronometrist-tag-choice`, and `chronometrist-key-values-unified-choice`, with more to come.
+* `chronometrist-reset`, to clear all internal state
 ### Removed
 * `chronometrist-skip-query-prompt`, `chronometrist-skip-query-reset`, and `chronometrist--skip-detail-prompts` - these are covered by the new single key prompt functions
 
diff --git a/elisp/chronometrist.el b/elisp/chronometrist.el
index a141a70..eb76047 100644
--- a/elisp/chronometrist.el
+++ b/elisp/chronometrist.el
@@ -450,6 +450,14 @@ file names respectively."
         (chronometrist-migrate-timelog-file-to-sexp-file timeclock-file chronometrist-file)
       (message "You can migrate later using `chronometrist-migrate-timelog-file-to-sexp-file'."))))
 
+(defun chronometrist-reset ()
+  "Reset Chronometrist's internal state."
+  (interactive)
+  (chronometrist-reset-task-list)
+  (chronometrist-events-populate)
+  (setq chronometrist--file-state nil)
+  (chronometrist-refresh))
+
 (defvar chronometrist-events (make-hash-table :test #'equal)
   "Each key is a date in the form (YEAR MONTH DAY).
 Values are lists containing events, where each event is a list in
diff --git a/elisp/chronometrist.org b/elisp/chronometrist.org
index b70705e..f951fe8 100644
--- a/elisp/chronometrist.org
+++ b/elisp/chronometrist.org
@@ -602,6 +602,16 @@ file names respectively."
       (message "You can migrate later using `chronometrist-migrate-timelog-file-to-sexp-file'."))))
 #+END_SRC
 *** Data structures
+**** reset-state                                                 :command:
+#+BEGIN_SRC emacs-lisp
+(defun chronometrist-reset ()
+  "Reset Chronometrist's internal state."
+  (interactive)
+  (chronometrist-reset-task-list)
+  (chronometrist-events-populate)
+  (setq chronometrist--file-state nil)
+  (chronometrist-refresh))
+#+END_SRC
 **** chronometrist-events                                                   :variable:
 :PROPERTIES:
 :VALUE:    hash table