 15. Personality Development in Adulthood and Later Life  339
Empirical Work on  Personality Development 
in Adulthood
Speculating about world or national meta 
trajectories of personality is splendid aca -
demic fun, but all of the empirical work is 
at the two lower tiers of our framework: 
person-  level and sample-  level trajectories. 
What does that work tell us? Since the turn 
of the millennium, there have been a number 
of studies utilizing Big Five traits that have 
used some form of trajectory model (latent 
growth or multilevel change models), and 
all have identified individual differences in 
not only level but also rates of change (Kan -
dler, Kornadt, Hagemeyer, & Neyer, 2015; 
Mroczek & Spiro, 2003; Terraciano, Costa, 
& McCrae, 2006), illustrating the bottom 
tier of our framework: person-  level trajecto -
ries. In addition, the middle tier of the frame -
work, sample-  level trajectories, illustrated by 
many researchers, have either plotted means 
over different ages (Bleidorn et al., 2013; 
Robins, Fraley, Roberts, & Treszesniewski, 
2001) or carried out longitudinal multilevel 
modeling (MLM) or latent growth models 
to estimate sample-  level trajectories. These 
researchers have found that during emerg -
ing adulthood and midlife, agreeableness, 
conscientiousness, openness, and extraver -
sion tend to increase, and neuroticism tends 
to decrease (Jones & Meredith, 1996; Lucas 
& Donnellan, 2011; Marsh, Nagengast, & 
Morin, 2013; Roberts & Mroczek, 2008; 
Roberts, Walton, & Viechtbauer, 2006; 
Terraciano, McCrae, Brant & Costa, 2005; 
Vaidya, Gray, Haig, Mroczek, & Watson, 
2008). Interestingly, Srivastava, John, Gos -
ling, and Potter (2003) largely found these 
same patterns, but identified evidence for 
accelerations (e.g., agreeableness) or decel -
erations (e.g., conscientiousness) in different 
segments of early adulthood.
After midlife, these overall trajectories 
shift somewhat, with various studies show -
ing decreases in all of the Big Five traits 
(Berg & Johannsson, 2014; Asendorpf, 
Denissen, & van Aken, 2008; Kandler et al., 
2015; Lucas & Donnellan, 2011; Mõttus, 
Johnson, & Deary, 2012; Roberts & Mroc -
zek, 2008; Terraciano et al., 2006; Wagner, 
Ram, Smith, & Gerstorf, 2016). These find -
ings imply curvilinearity over the course of adulthood, with many traits undergoing two 
distinct bends in the lifespan curve. Early 
adult increases and late life decreases are 
also consistent with two theoretical perspec -
tives we discuss below (the maturity princi -
ple and the selective optimization and com -
pensation effect; Roberts, Wood, & Caspi, 
2008; Kandler et al., 2015; Mueller et al., 
2016; Marsh et al., 2013).
These findings also align with the most 
comprehensive meta-  analysis of mean-level 
change in traits (Roberts et al., 2006), which 
indicated that certain traits (e.g., openness 
and conscientiousness) do seem to show 
a lifespan curvilinear effect, with peak at 
midlife or, in some cases, a quadratic effect 
in which increases decelerate or even flatten 
in older adulthood. The empirical work on 
traits seems to argue for increases in the ear -
lier part of adulthood, perhaps followed by 
midlife stability, but then decreases in older 
adulthood (Specht et al., 2014).
Outside of the personality trait domain, 
there are fewer examples of trajectory mod -
els, with the most notable exceptions in the 
areas of life satisfaction (Mroczek & Spiro, 
2005), affect (Charles, Reynolds, & Gatz, 
2001; Griffin, Mroczek, & Spiro, 2006; 
Orth, Robins, & Soto, 2010), and self- 
esteem (Orth & Robins, 2014; Mund & 
Neyer, 2016; Trzesniew  ski, Donnellan, & 
Robins, 2003; Wagner, Lüdtke, Jonkman, 
& Trautwein, 2013). Most other types of 
personality variables—  coping styles, nar -
rative constructs, goal striving, preferences 
and interests—  have not been studied in a 
long-term longitudinal manner in adult -
hood, with studies that obtain multiple 
measurement occasions. This will likely be 
corrected in the coming years with the use 
of online, device-  based data collection meth -
ods lowering the cost of expensive longitudi -
nal research designs.
In addition, the coming years are likely 
to see new trajectory models of personal -
ity trait facets. There have been remarkably 
few such studies, with Jackson et al. (2009) 
being one of the few (they evaluated change 
in conscientiousness facets). The Big Five has 
had a good run and will still play a central 
role in personality development research, 
but there is growing recognition that a finer- 
grained set of subtraits (facets, nuances, 