diff --git a/calendar/teachingdates/app.py b/calendar/teachingdates/app.py
index 121c1bf..d306da6 100644
--- a/calendar/teachingdates/app.py
+++ b/calendar/teachingdates/app.py
@@ -5,41 +5,35 @@
 
 from teachingdates import PROG
 import teachingdates.calendars as calendars
-import teachingdates.config as config
+import teachingdates.config as configuration
 
 
 def run():
-    args = config.parse_command_line()
+    args = configuration.parse_command_line()
     if args.debug:
         print("{prog}: debug: args: {a}".format(prog=PROG, a=args))
 
     try:
-        period_config, paper_config = config.parse_config(args.config, args)
+        config = configuration.Configuration(args)
         if args.debug:
             print("{prog}: debug: period config: {c}".format(
-                prog=PROG, c=period_config))
+                prog=PROG, c=config.get_period_config()))
             print("{prog}: debug: paper config: {c}".format(
-                prog=PROG, c=paper_config))
-        # priority: year on command line (defaults to current year),
-        # year in config
-        if period_config:
-            args.year = (
-                args.config["year"] if "year" in args.config.keys()
-                else args.year)
+                prog=PROG, c=config.get_paper_config()))
         cal = calendars.TeachingCalendar(
-            args.year, args.period, args.paper,
-            period_config, paper_config)
+            config.year, config.period, config.paper,
+            config.get_period_config(), config.get_paper_config())
         print("Period = {p}".format(p=args.period))
         print(cal.calendar())
         print(cal.lecture_dates())
-    except config.LectureStyleError as e:
+    except configuration.LectureStyleError as e:
         print("{prog}: error: 'lecture' style was requested but "
             "{c} contains no papers for {t}.".format(
                 prog=PROG, c=args.config, t=args.period))
-    except config.PaperError as e:
+    except configuration.PaperError as e:
         print("{prog}: error: no entry in {c} for paper {p} ({t}).".format(
             prog=PROG, c=args.config, p=args.paper, t=args.period))
-    except config.PeriodError as e:
+    except configuration.PeriodError as e:
         print("{prog}: error: no entry in {c} for teaching "
             "period {p}.".format(
                 prog=PROG, c=args.config_file, p=args.period))